primitives: split WitnessScript and WitnessScriptBuf from script

diff --git a/bitcoin/examples/script.rs b/bitcoin/examples/script.rs
index 09ecef3a..5198b58c 100644
--- a/bitcoin/examples/script.rs
+++ b/bitcoin/examples/script.rs
@@ -10,7 +10,7 @@
 use bitcoin::consensus::encode;
 use bitcoin::key::WPubkeyHash;
 use bitcoin::script::{self, GenericScriptBufExt as _, GenericScriptExt as _};
-use bitcoin::ScriptBuf;
+use bitcoin::{ScriptBuf, WitnessScriptBuf};
 
 fn main() {
     let pk = "b472a266d0bd89c13706a4132ccfb16f7c3b9fcb".parse::<WPubkeyHash>().unwrap();
@@ -18,13 +18,13 @@ fn main() {
     // TL;DR Use `to_hex_string_prefixed` and `from_hex_prefixed`.
     let script_code = script::p2wpkh_script_code(pk);
     let hex = script_code.to_hex_string_prefixed();
-    let decoded = ScriptBuf::from_hex_prefixed(&hex).unwrap();
+    let decoded = WitnessScriptBuf::from_hex_prefixed(&hex).unwrap();
     assert_eq!(decoded, script_code);
 
     // Or if you prefer: `to_hex_string_no_length_prefix` and `from_hex_no_length_prefix`.
     let script_code = script::p2wpkh_script_code(pk);
     let hex = script_code.to_hex_string_no_length_prefix();
-    let decoded = ScriptBuf::from_hex_no_length_prefix(&hex).unwrap();
+    let decoded = WitnessScriptBuf::from_hex_no_length_prefix(&hex).unwrap();
     assert_eq!(decoded, script_code);
 
     // Writes the script as human-readable eg, OP_DUP OP_HASH160 OP_PUSHBYTES_20 ...
@@ -42,39 +42,42 @@ fn main() {
     // And so does `from_hex_prefixed`.
     assert!(ScriptBuf::from_hex_prefixed(&hex_lower_hex_trait).is_err());
     // But we provide an explicit constructor that does not.
-    assert_eq!(ScriptBuf::from_hex_no_length_prefix(&hex_lower_hex_trait).unwrap(), script_code);
+    assert_eq!(
+        WitnessScriptBuf::from_hex_no_length_prefix(&hex_lower_hex_trait).unwrap(),
+        script_code
+    );
 
     // This is consensus encoding i.e., includes the length prefix.
     let hex_inherent = script_code.to_hex_string_prefixed(); // Defined in `ScriptExt`.
     println!("hex created using inherent `to_hex_string_prefixed`: {hex_inherent}");
 
     // The inverse of `to_hex_string_prefixed` is `from_hex_string_prefixed`.
-    let decoded = ScriptBuf::from_hex_prefixed(&hex_inherent).unwrap(); // Defined in `ScriptBufExt`.
+    let decoded = WitnessScriptBuf::from_hex_prefixed(&hex_inherent).unwrap(); // Defined in `ScriptBufExt`.
     assert_eq!(decoded, script_code);
     // We can also parse the output of `to_hex_string_prefixed` using `deserialize_hex`.
-    let decoded = encode::deserialize_hex::<ScriptBuf>(&hex_inherent).unwrap();
+    let decoded = encode::deserialize_hex::<WitnessScriptBuf>(&hex_inherent).unwrap();
     assert_eq!(decoded, script_code);
 
     // We also support encode/decode using `consensus::encode` functions.
     let encoded = encode::serialize_hex(&script_code);
     println!("hex created using consensus::encode::serialize_hex: {encoded}");
 
-    let decoded: ScriptBuf = encode::deserialize_hex(&encoded).unwrap();
+    let decoded: WitnessScriptBuf = encode::deserialize_hex(&encoded).unwrap();
     assert_eq!(decoded, script_code);
 
     // And we can mix these to calls because both include the length prefix.
     let encoded = encode::serialize_hex(&script_code);
-    let decoded = ScriptBuf::from_hex_prefixed(&encoded).unwrap();
+    let decoded = WitnessScriptBuf::from_hex_prefixed(&encoded).unwrap();
     assert_eq!(decoded, script_code);
 
     // Encode/decode using a byte vector.
     let encoded = encode::serialize(&script_code);
     assert_eq!(&encoded[1..], script_code.as_bytes()); // Shows that prefix is the first byte.
-    let decoded: ScriptBuf = encode::deserialize(&encoded).unwrap();
+    let decoded: WitnessScriptBuf = encode::deserialize(&encoded).unwrap();
     assert_eq!(decoded, script_code);
 
     // to/from bytes excludes the prefix, these are not encoding/decoding functions so this is sane.
     let bytes = script_code.to_bytes();
-    let got = ScriptBuf::from_bytes(bytes);
+    let got = WitnessScriptBuf::from_bytes(bytes);
     assert_eq!(got, script_code);
 }
diff --git a/bitcoin/examples/sighash.rs b/bitcoin/examples/sighash.rs
index 52f2a681..e25f267c 100644
--- a/bitcoin/examples/sighash.rs
+++ b/bitcoin/examples/sighash.rs
@@ -1,7 +1,7 @@
 use bitcoin::ext::*;
 use bitcoin::{
-    consensus, ecdsa, sighash, Amount, CompressedPublicKey, Script, ScriptPubKey, ScriptPubKeyBuf,
-    Transaction,
+    consensus, ecdsa, sighash, Amount, CompressedPublicKey, ScriptPubKey, ScriptPubKeyBuf,
+    Transaction, WitnessScript,
 };
 use hex_lit::hex;
 
@@ -112,7 +112,7 @@ fn compute_sighash_p2wsh(raw_tx: &[u8], inp_idx: usize, amount: Amount) {
 
     //last element is called witnessScript according to BIP-0141. It supersedes scriptPubKey.
     let witness_script_bytes: &[u8] = witness.last().expect("out of bounds");
-    let witness_script = Script::from_bytes(witness_script_bytes);
+    let witness_script = WitnessScript::from_bytes(witness_script_bytes);
     let mut cache = sighash::SighashCache::new(&tx);
 
     //in an M of N multisig, the witness elements from 1 (0-based) to M-2 are signatures (with sighash flags as the last byte)
diff --git a/bitcoin/src/address/mod.rs b/bitcoin/src/address/mod.rs
index c73a4363..af262d55 100644
--- a/bitcoin/src/address/mod.rs
+++ b/bitcoin/src/address/mod.rs
@@ -64,9 +64,10 @@ use crate::prelude::{String, ToOwned};
 use crate::script::witness_program::WitnessProgram;
 use crate::script::witness_version::WitnessVersion;
 use crate::script::{
-    self, GenericScript, GenericScriptExt as _, RedeemScriptSizeError, Script, ScriptExt as _,
-    ScriptHash, ScriptHashableTag, ScriptPubKey, ScriptPubKeyBuf, ScriptPubKeyBufExt as _,
-    ScriptPubKeyExt as _, WScriptHash, WitnessScriptSizeError,
+    self, GenericScript, GenericScriptExt as _, RedeemScriptSizeError, ScriptHash,
+    ScriptHashableTag, ScriptPubKey, ScriptPubKeyBuf, ScriptPubKeyBufExt as _,
+    ScriptPubKeyExt as _, WScriptHash, WitnessScript, WitnessScriptExt as _,
+    WitnessScriptSizeError,
 };
 use crate::taproot::TapNodeHash;
 
@@ -544,7 +545,7 @@ impl Address {
 
     /// Constructs a new pay-to-witness-script-hash (P2WSH) [`Address`] from a witness script.
     pub fn p2wsh(
-        witness_script: &Script,
+        witness_script: &WitnessScript,
         hrp: impl Into<KnownHrp>,
     ) -> Result<Address, WitnessScriptSizeError> {
         let program = WitnessProgram::p2wsh(witness_script)?;
@@ -562,7 +563,7 @@ impl Address {
     ///
     /// This is a SegWit address type that looks familiar (as p2sh) to legacy clients.
     pub fn p2shwsh(
-        witness_script: &Script,
+        witness_script: &WitnessScript,
         network: impl Into<NetworkKind>,
     ) -> Result<Address, WitnessScriptSizeError> {
         let hash = witness_script.wscript_hash()?;
@@ -1021,7 +1022,7 @@ mod tests {
     use super::*;
     use crate::network::Network::{Bitcoin, Testnet};
     use crate::network::{params, TestnetVersion};
-    use crate::script::{GenericScriptBufExt as _, RedeemScriptBuf, ScriptBuf};
+    use crate::script::{GenericScriptBufExt as _, RedeemScriptBuf, WitnessScriptBuf};
 
     fn roundtrips(addr: &Address, network: Network) {
         assert_eq!(
@@ -1127,7 +1128,7 @@ mod tests {
     #[test]
     fn p2wsh() {
         // stolen from Bitcoin transaction 5df912fda4becb1c29e928bec8d64d93e9ba8efa9b5b405bd683c86fd2c65667
-        let script = ScriptBuf::from_hex_no_length_prefix("52210375e00eb72e29da82b89367947f29ef34afb75e8654f6ea368e0acdfd92976b7c2103a1b26313f430c4b15bb1fdce663207659d8cac749a0e53d70eff01874496feff2103c96d495bfdd5ba4145e3e046fee45e84a8a48ad05bd8dbb395c011a32cf9f88053ae").unwrap();
+        let script = WitnessScriptBuf::from_hex_no_length_prefix("52210375e00eb72e29da82b89367947f29ef34afb75e8654f6ea368e0acdfd92976b7c2103a1b26313f430c4b15bb1fdce663207659d8cac749a0e53d70eff01874496feff2103c96d495bfdd5ba4145e3e046fee45e84a8a48ad05bd8dbb395c011a32cf9f88053ae").unwrap();
         let addr = Address::p2wsh(&script, KnownHrp::Mainnet).expect("script is valid");
         assert_eq!(
             &addr.to_string(),
@@ -1152,7 +1153,7 @@ mod tests {
     #[test]
     fn p2shwsh() {
         // stolen from Bitcoin transaction f9ee2be4df05041d0e0a35d7caa3157495ca4f93b233234c9967b6901dacf7a9
-        let script = ScriptBuf::from_hex_no_length_prefix("522103e5529d8eaa3d559903adb2e881eb06c86ac2574ffa503c45f4e942e2a693b33e2102e5f10fcdcdbab211e0af6a481f5532536ec61a5fdbf7183770cf8680fe729d8152ae").unwrap();
+        let script = WitnessScriptBuf::from_hex_no_length_prefix("522103e5529d8eaa3d559903adb2e881eb06c86ac2574ffa503c45f4e942e2a693b33e2102e5f10fcdcdbab211e0af6a481f5532536ec61a5fdbf7183770cf8680fe729d8152ae").unwrap();
         let addr = Address::p2shwsh(&script, NetworkKind::Main).expect("script is valid");
         assert_eq!(&addr.to_string(), "36EqgNnsWW94SreZgBWc1ANC6wpFZwirHr");
         assert_eq!(addr.address_type(), Some(AddressType::P2sh));
diff --git a/bitcoin/src/blockdata/script/borrowed.rs b/bitcoin/src/blockdata/script/borrowed.rs
index c70de812..d69d09bd 100644
--- a/bitcoin/src/blockdata/script/borrowed.rs
+++ b/bitcoin/src/blockdata/script/borrowed.rs
@@ -11,7 +11,7 @@ use super::witness_version::WitnessVersion;
 use super::{
     Builder, GenericScript, Instruction, InstructionIndices, Instructions, PushBytes, RedeemScript,
     RedeemScriptSizeError, Script, ScriptHash, ScriptHashableTag, ScriptPubKey, ScriptSig,
-    WScriptHash, WitnessScriptSizeError,
+    WScriptHash, WitnessScript, WitnessScriptSizeError,
 };
 use crate::consensus::{self, Encodable};
 use crate::key::{PublicKey, UntweakedPublicKey, WPubkeyHash};
@@ -21,7 +21,7 @@ use crate::policy::{DUST_RELAY_TX_FEE, MAX_OP_RETURN_RELAY};
 use crate::prelude::{sink, String, ToString};
 use crate::script::{self, ScriptPubKeyBufExt as _};
 use crate::taproot::{LeafVersion, TapLeafHash, TapNodeHash};
-use crate::{internal_macros, Amount, FeeRate, ScriptBuf, ScriptPubKeyBuf};
+use crate::{internal_macros, Amount, FeeRate, ScriptPubKeyBuf, WitnessScriptBuf};
 
 internal_macros::define_extension_trait! {
     /// Extension functionality for the [`Script`] type.
@@ -178,8 +178,12 @@ internal_macros::define_extension_trait! {
         /// Returns the script code used for spending a P2WPKH output if this script is a script pubkey
         /// for a P2WPKH output. The `scriptCode` is described in [BIP-0143].
         ///
+        /// While the type returned is [`WitnessScriptBuf`], this is **not** a witness script and
+        /// should not be used as one. It is a special template defined in BIP 143 which is used
+        /// in place of a witness script for purposes of sighash computation.
+        ///
         /// [BIP-0143]: <https://github.com/bitcoin/bips/blob/99701f68a88ce33b2d0838eb84e115cef505b4c2/bip-0143.mediawiki>
-        fn p2wpkh_script_code(&self) -> Option<ScriptBuf>
+        fn p2wpkh_script_code(&self) -> Option<WitnessScriptBuf>
         where T: ScriptHashableTag
         {
             if self.is_p2wpkh() {
@@ -249,25 +253,30 @@ internal_macros::define_extension_trait! {
 
 internal_macros::define_extension_trait! {
     /// Extension functionality for the [`Script`] type.
-    pub trait ScriptExt impl for Script {
+    pub trait WitnessScriptExt impl for WitnessScript {
         /// Returns 256-bit hash of the script for P2WSH outputs.
         #[inline]
         fn wscript_hash(&self) -> Result<WScriptHash, WitnessScriptSizeError> {
             WScriptHash::from_script(self)
         }
 
+        /// Computes the P2WSH output corresponding to this witnessScript (aka the "witness redeem
+        /// script").
+        fn to_p2wsh(&self) -> Result<ScriptPubKeyBuf, WitnessScriptSizeError> {
+            self.wscript_hash().map(ScriptPubKeyBuf::new_p2wsh)
+        }
+    }
+}
+
+crate::internal_macros::define_extension_trait! {
+    /// Extension functionality for the [`Script`] type.
+    pub trait ScriptExt impl for Script {
         /// Computes leaf hash of tapscript.
         #[inline]
         fn tapscript_leaf_hash(&self) -> TapLeafHash {
             TapLeafHash::from_script(self, LeafVersion::TapScript)
         }
 
-        /// Computes the P2WSH output corresponding to this witnessScript (aka the "witness redeem
-        /// script").
-        fn to_p2wsh(&self) -> Result<ScriptPubKeyBuf, WitnessScriptSizeError> {
-            self.wscript_hash().map(ScriptPubKeyBuf::new_p2wsh)
-      }
-
         /// Computes P2TR output with a given internal key and a single script spending path equal to
         /// the current script, assuming that the script is a Tapscript.
         fn to_p2tr<C: Verification, K: Into<UntweakedPublicKey>>(
diff --git a/bitcoin/src/blockdata/script/mod.rs b/bitcoin/src/blockdata/script/mod.rs
index aac2d030..18895d7e 100644
--- a/bitcoin/src/blockdata/script/mod.rs
+++ b/bitcoin/src/blockdata/script/mod.rs
@@ -74,7 +74,7 @@ use crate::OutPoint;
 #[rustfmt::skip]                // Keep public re-exports separate.
 #[doc(inline)]
 pub use self::{
-    borrowed::{GenericScriptExt, ScriptExt, ScriptPubKeyExt, ScriptSigExt},
+    borrowed::{GenericScriptExt, ScriptExt, ScriptPubKeyExt, WitnessScriptExt, ScriptSigExt},
     builder::Builder,
     instruction::{Instruction, Instructions, InstructionIndices},
     owned::{GenericScriptBufExt, ScriptPubKeyBufExt},
@@ -85,7 +85,7 @@ pub use primitives::script::{
     GenericScript, GenericScriptBuf, RedeemScript, RedeemScriptBuf, RedeemScriptSizeError,
     RedeemScriptTag, Script, ScriptBuf, ScriptHash, ScriptHashableTag, ScriptPubKey,
     ScriptPubKeyBuf, ScriptPubKeyTag, ScriptSig, ScriptSigBuf, ScriptSigTag, Tag, WScriptHash,
-    Whatever, WitnessScriptSizeError,
+    Whatever, WitnessScript, WitnessScriptBuf, WitnessScriptSizeError, WitnessScriptTag,
 };
 
 pub(crate) use self::borrowed::GenericScriptExtPriv;
@@ -97,8 +97,12 @@ impl_asref_push_bytes!(ScriptHash, WScriptHash);
 ///
 /// The `scriptCode` is described in [BIP-0143].
 ///
+/// While the type returned is [`WitnessScriptBuf`], this is **not** a witness script and
+/// should not be used as one. It is a special template defined in BIP-0143 which is used
+/// in place of a witness script for purposes of sighash computation.
+///
 /// [BIP-0143]: <https://github.com/bitcoin/bips/blob/99701f68a88ce33b2d0838eb84e115cef505b4c2/bip-0143.mediawiki>
-pub fn p2wpkh_script_code(wpkh: WPubkeyHash) -> ScriptBuf {
+pub fn p2wpkh_script_code(wpkh: WPubkeyHash) -> WitnessScriptBuf {
     Builder::new()
         .push_opcode(OP_DUP)
         .push_opcode(OP_HASH160)
diff --git a/bitcoin/src/blockdata/script/tests.rs b/bitcoin/src/blockdata/script/tests.rs
index f7a8245e..5a7b382c 100644
--- a/bitcoin/src/blockdata/script/tests.rs
+++ b/bitcoin/src/blockdata/script/tests.rs
@@ -246,7 +246,7 @@ fn script_generators() {
     assert!(p2sh.is_p2sh());
     assert_eq!(script.to_p2sh().unwrap(), p2sh);
 
-    let script = Script::builder().push_opcode(OP_NUMEQUAL).push_verify().into_script();
+    let script = WitnessScript::builder().push_opcode(OP_NUMEQUAL).push_verify().into_script();
     let wscript_hash = script.wscript_hash().expect("script is less than 10,000 bytes");
     let p2wsh = ScriptPubKeyBuf::new_p2wsh(wscript_hash);
     assert!(p2wsh.is_p2wsh());
@@ -402,7 +402,7 @@ fn script_hashes() {
         script.script_hash().unwrap().to_string(),
         "8292bcfbef1884f73c813dfe9c82fd7e814291ea"
     );
-    let script = ScriptBuf::from_hex_no_length_prefix("410446ef0102d1ec5240f0d061a4246c1bdef63fc3dbab7733052fbbf0ecd8f41fc26bf049ebb4f9527f374280259e7cfa99c48b0e3f39c51347a19a5819651503a5ac").unwrap();
+    let script = WitnessScriptBuf::from_hex_no_length_prefix("410446ef0102d1ec5240f0d061a4246c1bdef63fc3dbab7733052fbbf0ecd8f41fc26bf049ebb4f9527f374280259e7cfa99c48b0e3f39c51347a19a5819651503a5ac").unwrap();
     assert_eq!(
         script.wscript_hash().unwrap().to_string(),
         "3e1525eb183ad4f9b3c5fa3175bdca2a52e947b135bbb90383bf9f6408e2c324"
@@ -624,7 +624,7 @@ fn script_p2pk() {
 fn p2sh_p2wsh_conversion() {
     // Test vectors taken from Core tests/data/script_tests.json
     // bare p2wsh
-    let witness_script = ScriptBuf::from_hex_no_length_prefix("410479be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8ac").unwrap();
+    let witness_script = WitnessScriptBuf::from_hex_no_length_prefix("410479be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8ac").unwrap();
     let expected_without = ScriptPubKeyBuf::from_hex_no_length_prefix(
         "0020b95237b48faaa69eb078e1170be3b5cbb3fddf16d0a991e14ad274f7b33a4f64",
     )
@@ -642,7 +642,7 @@ fn p2sh_p2wsh_conversion() {
     assert_eq!(redeem_script.to_p2sh().unwrap(), expected_p2shout);
 
     // p2sh-p2wsh
-    let witness_script = ScriptBuf::from_hex_no_length_prefix("410479be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8ac").unwrap();
+    let witness_script = WitnessScriptBuf::from_hex_no_length_prefix("410479be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8ac").unwrap();
     let expected_without = ScriptPubKeyBuf::from_hex_no_length_prefix(
         "0020b95237b48faaa69eb078e1170be3b5cbb3fddf16d0a991e14ad274f7b33a4f64",
     )
diff --git a/bitcoin/src/blockdata/script/witness_program.rs b/bitcoin/src/blockdata/script/witness_program.rs
index 05c5c93c..e43e12c3 100644
--- a/bitcoin/src/blockdata/script/witness_program.rs
+++ b/bitcoin/src/blockdata/script/witness_program.rs
@@ -14,9 +14,9 @@ use internals::array_vec::ArrayVec;
 use secp256k1::{Secp256k1, Verification};
 
 use super::witness_version::WitnessVersion;
-use super::{PushBytes, Script, WScriptHash, WitnessScriptSizeError};
+use super::{PushBytes, WScriptHash, WitnessScript, WitnessScriptSizeError};
 use crate::crypto::key::{CompressedPublicKey, TapTweak, TweakedPublicKey, UntweakedPublicKey};
-use crate::script::ScriptExt as _;
+use crate::script::WitnessScriptExt as _;
 use crate::taproot::TapNodeHash;
 
 /// The minimum byte size of a segregated witness program.
@@ -82,7 +82,7 @@ impl WitnessProgram {
     }
 
     /// Constructs a new [`WitnessProgram`] from `script` for a P2WSH output.
-    pub fn p2wsh(script: &Script) -> Result<Self, WitnessScriptSizeError> {
+    pub fn p2wsh(script: &WitnessScript) -> Result<Self, WitnessScriptSizeError> {
         script.wscript_hash().map(Self::p2wsh_from_hash)
     }
 
diff --git a/bitcoin/src/blockdata/witness.rs b/bitcoin/src/blockdata/witness.rs
index ad820601..cb5d4dcf 100644
--- a/bitcoin/src/blockdata/witness.rs
+++ b/bitcoin/src/blockdata/witness.rs
@@ -15,7 +15,7 @@ use crate::prelude::Vec;
 #[cfg(doc)]
 use crate::script::ScriptExt as _;
 use crate::taproot::{self, ControlBlock, LeafScript, TaprootMerkleBranch, TAPROOT_ANNEX_PREFIX};
-use crate::{internal_macros, Script};
+use crate::{internal_macros, Script, WitnessScript};
 
 type BorrowedControlBlock<'a> = ControlBlock<&'a TaprootMerkleBranch, &'a SerializedXOnlyPublicKey>;
 
@@ -210,8 +210,7 @@ internal_macros::define_extension_trait! {
         /// witness script: it may be a Taproot control block, annex, or some other kind
         /// of object. If you are not certain whether the output being spent is Segwit v0,
         /// use [`crate::script::GenericScriptExt::is_p2wsh`] on the output's script.
-        fn witness_script(&self) -> Option<&Script> { self.last().map(Script::from_bytes) }
-
+        fn witness_script(&self) -> Option<&WitnessScript> { self.last().map(WitnessScript::from_bytes) }
     }
 }
 
diff --git a/bitcoin/src/crypto/key.rs b/bitcoin/src/crypto/key.rs
index 9a706347..8427a800 100644
--- a/bitcoin/src/crypto/key.rs
+++ b/bitcoin/src/crypto/key.rs
@@ -21,7 +21,7 @@ use crate::crypto::ecdsa;
 use crate::internal_macros::impl_asref_push_bytes;
 use crate::network::NetworkKind;
 use crate::prelude::{DisplayHex, String, Vec};
-use crate::script::{self, ScriptBuf};
+use crate::script::{self, WitnessScriptBuf};
 use crate::taproot::{TapNodeHash, TapTweakHash};
 
 #[rustfmt::skip]                // Keep public re-exports separate.
@@ -185,7 +185,11 @@ impl PublicKey {
     }
 
     /// Returns the script code used to spend a P2WPKH input.
-    pub fn p2wpkh_script_code(&self) -> Result<ScriptBuf, UncompressedPublicKeyError> {
+    ///
+    /// While the type returned is [`WitnessScriptBuf`], this is **not** a witness script and
+    /// should not be used as one. It is a special template defined in BIP 143 which is used
+    /// in place of a witness script for purposes of sighash computation.
+    pub fn p2wpkh_script_code(&self) -> Result<WitnessScriptBuf, UncompressedPublicKeyError> {
         let key = CompressedPublicKey::try_from(*self)?;
         Ok(key.p2wpkh_script_code())
     }
@@ -404,7 +408,11 @@ impl CompressedPublicKey {
     }
 
     /// Returns the script code used to spend a P2WPKH input.
-    pub fn p2wpkh_script_code(&self) -> ScriptBuf {
+    ///
+    /// While the type returned is [`WitnessScriptBuf`], this is **not** a witness script and
+    /// should not be used as one. It is a special template defined in BIP 143 which is used
+    /// in place of a witness script for purposes of sighash computation.
+    pub fn p2wpkh_script_code(&self) -> WitnessScriptBuf {
         script::p2wpkh_script_code(self.wpubkey_hash())
     }
 
diff --git a/bitcoin/src/crypto/sighash.rs b/bitcoin/src/crypto/sighash.rs
index 53de5e26..088fe085 100644
--- a/bitcoin/src/crypto/sighash.rs
+++ b/bitcoin/src/crypto/sighash.rs
@@ -26,7 +26,9 @@ use crate::script::{GenericScriptExt as _, ScriptHashableTag};
 use crate::taproot::{LeafVersion, TapLeafHash, TapLeafTag, TAPROOT_ANNEX_PREFIX};
 use crate::transaction::TransactionExt as _;
 use crate::witness::Witness;
-use crate::{transaction, Amount, Script, ScriptPubKey, Sequence, Transaction, TxOut};
+use crate::{
+    transaction, Amount, Script, ScriptPubKey, Sequence, Transaction, TxOut, WitnessScript,
+};
 
 /// Used for signature hash for invalid use of SIGHASH_SINGLE.
 #[rustfmt::skip]
@@ -816,7 +818,7 @@ impl<R: Borrow<Transaction>> SighashCache<R> {
         &mut self,
         writer: &mut W,
         input_index: usize,
-        script_code: &Script,
+        script_code: &WitnessScript,
         value: Amount,
         sighash_type: EcdsaSighashType,
     ) -> Result<(), SigningDataError<transaction::InputsIndexError>> {
@@ -899,7 +901,7 @@ impl<R: Borrow<Transaction>> SighashCache<R> {
     pub fn p2wsh_signature_hash(
         &mut self,
         input_index: usize,
-        witness_script: &Script,
+        witness_script: &WitnessScript,
         value: Amount,
         sighash_type: EcdsaSighashType,
     ) -> Result<SegwitV0Sighash, transaction::InputsIndexError> {
@@ -1537,7 +1539,9 @@ mod tests {
     use super::*;
     use crate::consensus::deserialize;
     use crate::locktime::absolute;
-    use crate::script::{GenericScriptBufExt as _, ScriptBuf, ScriptPubKey, ScriptPubKeyBuf};
+    use crate::script::{
+        GenericScriptBufExt as _, ScriptBuf, ScriptPubKey, ScriptPubKeyBuf, WitnessScriptBuf,
+    };
     use crate::TxIn;
 
     extern crate serde_json;
@@ -2170,7 +2174,7 @@ mod tests {
     // Note, if you are looking at the test vectors in BIP-0143 and wondering why there is a `cf`
     // prepended to all the script_code hex it is the length byte, it gets added when we consensus
     // encode a script.
-    fn bip143_p2wsh_nested_in_p2sh_data() -> (Transaction, ScriptBuf, Amount) {
+    fn bip143_p2wsh_nested_in_p2sh_data() -> (Transaction, WitnessScriptBuf, Amount) {
         let tx = deserialize::<Transaction>(&hex!(
             "010000000136641869ca081e70f394c6948e8af409e18b619df2ed74aa106c1ca29787b96e0100000000\
              ffffffff0200e9a435000000001976a914389ffce9cd9ae88dcc0631e88a821ffdbe9bfe2688acc0832f\
@@ -2178,7 +2182,7 @@ mod tests {
         ))
         .unwrap();
 
-        let witness_script = ScriptBuf::from_hex_no_length_prefix(
+        let witness_script = WitnessScriptBuf::from_hex_no_length_prefix(
             "56210307b8ae49ac90a048e9b53357a2354b3334e9c8bee813ecb98e99a7e07e8c3ba32103b28f0c28\
              bfab54554ae8c658ac5c3e0ce6e79ad336331f78c428dd43eea8449b21034b8113d703413d57761b8b\
              9781957b8c0ac1dfe69f492580ca4195f50376ba4a21033400f6afecb833092a9a21cfdf1ed1376e58\
diff --git a/bitcoin/src/lib.rs b/bitcoin/src/lib.rs
index e732ff2d..66755b2b 100644
--- a/bitcoin/src/lib.rs
+++ b/bitcoin/src/lib.rs
@@ -114,7 +114,7 @@ pub mod ext {
     pub use crate::{
         block::{BlockUncheckedExt as _, BlockCheckedExt as _, HeaderExt as _},
         pow::CompactTargetExt as _,
-        script::{GenericScriptExt as _, GenericScriptBufExt as _, ScriptExt as _, ScriptPubKeyExt as _, ScriptPubKeyBufExt as _, ScriptSigExt as _},
+        script::{GenericScriptExt as _, GenericScriptBufExt as _, ScriptExt as _, ScriptPubKeyExt as _, ScriptPubKeyBufExt as _, WitnessScriptExt as _, ScriptSigExt as _},
         transaction::{TxidExt as _, WtxidExt as _, OutPointExt as _, TxInExt as _, TxOutExt as _, TransactionExt as _},
         witness::WitnessExt as _,
     };
@@ -154,7 +154,7 @@ pub use primitives::{
     pow::CompactTarget, // No `pow` module outside of `primitives`.
     script::{
         RedeemScript, RedeemScriptBuf, Script, ScriptBuf, ScriptPubKey, ScriptPubKeyBuf, ScriptSig,
-        ScriptSigBuf,
+        ScriptSigBuf, WitnessScript, WitnessScriptBuf,
     },
     sequence::{self, Sequence}, // No `sequence` module outside of `primitives`.
     transaction::{OutPoint, Transaction, TxIn, TxOut, Txid, Version as TransactionVersion, Wtxid},
diff --git a/bitcoin/src/psbt/map/input.rs b/bitcoin/src/psbt/map/input.rs
index 16dfa131..7675bd78 100644
--- a/bitcoin/src/psbt/map/input.rs
+++ b/bitcoin/src/psbt/map/input.rs
@@ -12,7 +12,7 @@ use crate::prelude::{btree_map, BTreeMap, Borrow, Box, ToOwned, Vec};
 use crate::psbt::map::Map;
 use crate::psbt::serialize::Deserialize;
 use crate::psbt::{error, raw, Error};
-use crate::script::{RedeemScriptBuf, ScriptBuf, ScriptSigBuf};
+use crate::script::{RedeemScriptBuf, ScriptBuf, ScriptSigBuf, WitnessScriptBuf};
 use crate::sighash::{
     EcdsaSighashType, InvalidSighashTypeError, NonStandardSighashTypeError, SighashTypeParseError,
     TapSighashType,
@@ -85,7 +85,7 @@ pub struct Input {
     /// The redeem script for this input.
     pub redeem_script: Option<RedeemScriptBuf>,
     /// The witness script for this input.
-    pub witness_script: Option<ScriptBuf>,
+    pub witness_script: Option<WitnessScriptBuf>,
     /// A map from public keys needed to sign this input to their corresponding
     /// master key fingerprints and derivation paths.
     pub bip32_derivation: BTreeMap<secp256k1::PublicKey, KeySource>,
@@ -288,7 +288,7 @@ impl Input {
             }
             PSBT_IN_WITNESS_SCRIPT => {
                 impl_psbt_insert_pair! {
-                    self.witness_script <= <raw_key: _>|<raw_value: ScriptBuf>
+                    self.witness_script <= <raw_key: _>|<raw_value: WitnessScriptBuf>
                 }
             }
             PSBT_IN_BIP32_DERIVATION => {
diff --git a/bitcoin/src/psbt/map/output.rs b/bitcoin/src/psbt/map/output.rs
index 13e5543c..ad72f242 100644
--- a/bitcoin/src/psbt/map/output.rs
+++ b/bitcoin/src/psbt/map/output.rs
@@ -5,7 +5,7 @@ use crate::crypto::key::XOnlyPublicKey;
 use crate::prelude::{btree_map, BTreeMap, Vec};
 use crate::psbt::map::Map;
 use crate::psbt::{raw, Error};
-use crate::script::{RedeemScriptBuf, ScriptBuf};
+use crate::script::{RedeemScriptBuf, WitnessScriptBuf};
 use crate::taproot::{TapLeafHash, TapTree};
 
 /// Type: Redeem ScriptBuf PSBT_OUT_REDEEM_SCRIPT = 0x00
@@ -32,7 +32,7 @@ pub struct Output {
     /// The redeem script for this output.
     pub redeem_script: Option<RedeemScriptBuf>,
     /// The witness script for this output.
-    pub witness_script: Option<ScriptBuf>,
+    pub witness_script: Option<WitnessScriptBuf>,
     /// A map from public keys needed to spend this output to their
     /// corresponding master key fingerprints and derivation paths.
     pub bip32_derivation: BTreeMap<secp256k1::PublicKey, KeySource>,
@@ -62,7 +62,7 @@ impl Output {
             }
             PSBT_OUT_WITNESS_SCRIPT => {
                 impl_psbt_insert_pair! {
-                    self.witness_script <= <raw_key: _>|<raw_value: ScriptBuf>
+                    self.witness_script <= <raw_key: _>|<raw_value: WitnessScriptBuf>
                 }
             }
             PSBT_OUT_BIP32_DERIVATION => {
diff --git a/bitcoin/src/psbt/mod.rs b/bitcoin/src/psbt/mod.rs
index 8956f6ec..a3641a6c 100644
--- a/bitcoin/src/psbt/mod.rs
+++ b/bitcoin/src/psbt/mod.rs
@@ -1344,7 +1344,7 @@ mod tests {
     use crate::network::NetworkKind;
     use crate::psbt::serialize::{Deserialize, Serialize};
     use crate::script::{
-        GenericScriptBufExt as _, RedeemScriptBuf, ScriptBuf, ScriptPubKeyBuf, ScriptSigBuf,
+        GenericScriptBufExt as _, RedeemScriptBuf, ScriptPubKeyBuf, ScriptSigBuf, WitnessScriptBuf,
     };
     use crate::transaction::{self, OutPoint, TxIn};
     use crate::witness::Witness;
@@ -1521,7 +1521,7 @@ mod tests {
                 .unwrap(),
             ),
             witness_script: Some(
-                ScriptBuf::from_hex_no_length_prefix(
+                WitnessScriptBuf::from_hex_no_length_prefix(
                     "a9143545e6e33b832c47050f24d3eeb93c9c03948bc787",
                 )
                 .unwrap(),
diff --git a/primitives/src/lib.rs b/primitives/src/lib.rs
index 3e9523d0..7499c347 100644
--- a/primitives/src/lib.rs
+++ b/primitives/src/lib.rs
@@ -76,7 +76,7 @@ pub use self::{
     },
     script::{
         RedeemScript, RedeemScriptBuf, Script, ScriptBuf, ScriptPubKey, ScriptPubKeyBuf, ScriptSig,
-        ScriptSigBuf,
+        ScriptSigBuf, WitnessScript, WitnessScriptBuf,
     },
     transaction::{Transaction, TxIn, TxOut},
     witness::Witness,
diff --git a/primitives/src/script/mod.rs b/primitives/src/script/mod.rs
index 11ffab1a..5c87560e 100644
--- a/primitives/src/script/mod.rs
+++ b/primitives/src/script/mod.rs
@@ -30,7 +30,7 @@ use crate::prelude::{Borrow, BorrowMut, Box, Cow, ToOwned, Vec};
 pub use self::{
     borrowed::GenericScript,
     owned::GenericScriptBuf,
-    tag::{Tag, RedeemScriptTag, ScriptPubKeyTag, ScriptSigTag, Whatever},
+    tag::{Tag, RedeemScriptTag, ScriptPubKeyTag, ScriptSigTag, Whatever, WitnessScriptTag},
 };
 
 /// Placeholder doc (will be replaced in later commit)
@@ -57,6 +57,12 @@ pub type ScriptPubKeyBuf = GenericScriptBuf<ScriptPubKeyTag>;
 /// A script signature (scriptSig).
 pub type ScriptSigBuf = GenericScriptBuf<ScriptSigTag>;
 
+/// A Segwit v0 witness script.
+pub type WitnessScriptBuf = GenericScriptBuf<WitnessScriptTag>;
+
+/// A reference to a Segwit v0 witness script.
+pub type WitnessScript = GenericScript<WitnessScriptTag>;
+
 /// The maximum allowed redeem script size for a P2SH output.
 pub const MAX_REDEEM_SCRIPT_SIZE: usize = 520;
 /// The maximum allowed redeem script size of the witness script.
@@ -152,7 +158,7 @@ impl WScriptHash {
     ///
     /// ref: [BIP-141](https://github.com/bitcoin/bips/blob/master/bip-0141.mediawiki)
     #[inline]
-    pub fn from_script(witness_script: &Script) -> Result<Self, WitnessScriptSizeError> {
+    pub fn from_script(witness_script: &WitnessScript) -> Result<Self, WitnessScriptSizeError> {
         if witness_script.len() > MAX_WITNESS_SCRIPT_SIZE {
             return Err(WitnessScriptSizeError { size: witness_script.len() });
         }
@@ -168,7 +174,7 @@ impl WScriptHash {
     ///
     /// ref: [BIP-141](https://github.com/bitcoin/bips/blob/master/bip-0141.mediawiki)
     #[inline]
-    pub fn from_script_unchecked(script: &Script) -> Self {
+    pub fn from_script_unchecked(script: &WitnessScript) -> Self {
         WScriptHash(sha256::Hash::hash(script.as_bytes()))
     }
 }
@@ -200,29 +206,29 @@ impl<T: ScriptHashableTag> TryFrom<&GenericScript<T>> for ScriptHash {
     }
 }
 
-impl TryFrom<ScriptBuf> for WScriptHash {
+impl TryFrom<WitnessScriptBuf> for WScriptHash {
     type Error = WitnessScriptSizeError;
 
     #[inline]
-    fn try_from(witness_script: ScriptBuf) -> Result<Self, Self::Error> {
+    fn try_from(witness_script: WitnessScriptBuf) -> Result<Self, Self::Error> {
         Self::from_script(&witness_script)
     }
 }
 
-impl TryFrom<&ScriptBuf> for WScriptHash {
+impl TryFrom<&WitnessScriptBuf> for WScriptHash {
     type Error = WitnessScriptSizeError;
 
     #[inline]
-    fn try_from(witness_script: &ScriptBuf) -> Result<Self, Self::Error> {
+    fn try_from(witness_script: &WitnessScriptBuf) -> Result<Self, Self::Error> {
         Self::from_script(witness_script)
     }
 }
 
-impl TryFrom<&Script> for WScriptHash {
+impl TryFrom<&WitnessScript> for WScriptHash {
     type Error = WitnessScriptSizeError;
 
     #[inline]
-    fn try_from(witness_script: &Script) -> Result<Self, Self::Error> {
+    fn try_from(witness_script: &WitnessScript) -> Result<Self, Self::Error> {
         Self::from_script(witness_script)
     }
 }
@@ -767,23 +773,23 @@ mod tests {
 
     #[test]
     fn script_hash_from_script_unchecked() {
-        let script = Script::from_bytes(&[0x51; 521]);
+        let script = WitnessScript::from_bytes(&[0x51; 521]);
         let hash = ScriptHash::from_script_unchecked(script);
         assert_eq!(hash, ScriptHash(hash160::Hash::hash(script.as_bytes())));
     }
 
     #[test]
     fn wscript_hash_from_script() {
-        let script = Script::from_bytes(&[0x51; 10_000]);
+        let script = WitnessScript::from_bytes(&[0x51; 10_000]);
         assert!(WScriptHash::from_script(script).is_ok());
 
-        let script = Script::from_bytes(&[0x51; 10_001]);
+        let script = WitnessScript::from_bytes(&[0x51; 10_001]);
         assert!(WScriptHash::from_script(script).is_err());
     }
 
     #[test]
     fn wscript_hash_from_script_unchecked() {
-        let script = Script::from_bytes(&[0x51; 10_001]);
+        let script = WitnessScript::from_bytes(&[0x51; 10_001]);
         let hash = WScriptHash::from_script_unchecked(script);
         assert_eq!(hash, WScriptHash(sha256::Hash::hash(script.as_bytes())));
     }
@@ -817,28 +823,28 @@ mod tests {
 
     #[test]
     fn try_from_scriptbuf_for_wscript_hash() {
-        let script = ScriptBuf::from(vec![0x51; 10_000]);
+        let script = WitnessScriptBuf::from(vec![0x51; 10_000]);
         assert!(WScriptHash::try_from(script).is_ok());
 
-        let script = ScriptBuf::from(vec![0x51; 10_001]);
+        let script = WitnessScriptBuf::from(vec![0x51; 10_001]);
         assert!(WScriptHash::try_from(script).is_err());
     }
 
     #[test]
     fn try_from_scriptbuf_ref_for_wscript_hash() {
-        let script = ScriptBuf::from(vec![0x51; 10_000]);
+        let script = WitnessScriptBuf::from(vec![0x51; 10_000]);
         assert!(WScriptHash::try_from(&script).is_ok());
 
-        let script = ScriptBuf::from(vec![0x51; 10_001]);
+        let script = WitnessScriptBuf::from(vec![0x51; 10_001]);
         assert!(WScriptHash::try_from(&script).is_err());
     }
 
     #[test]
     fn try_from_script_for_wscript_hash() {
-        let script = Script::from_bytes(&[0x51; 10_000]);
+        let script = WitnessScript::from_bytes(&[0x51; 10_000]);
         assert!(WScriptHash::try_from(script).is_ok());
 
-        let script = Script::from_bytes(&[0x51; 10_001]);
+        let script = WitnessScript::from_bytes(&[0x51; 10_001]);
         assert!(WScriptHash::try_from(script).is_err());
     }
 
@@ -944,7 +950,7 @@ mod tests {
 
     #[test]
     fn witness_script_size_error() {
-        let script = ScriptBuf::from(vec![0x51; 10_001]);
+        let script = WitnessScriptBuf::from(vec![0x51; 10_001]);
         let result = WScriptHash::try_from(script);
 
         let err = result.unwrap_err();
diff --git a/primitives/src/script/tag.rs b/primitives/src/script/tag.rs
index 82b71fc6..fa70f174 100644
--- a/primitives/src/script/tag.rs
+++ b/primitives/src/script/tag.rs
@@ -28,3 +28,8 @@ impl Tag for ScriptSigTag {}
 #[derive(Clone, PartialOrd, Ord, PartialEq, Eq, Hash)]
 pub enum ScriptPubKeyTag {}
 impl Tag for ScriptPubKeyTag {}
+
+/// A Segwit v0 witness script.
+#[derive(Clone, PartialOrd, Ord, PartialEq, Eq, Hash)]
+pub enum WitnessScriptTag {}
+impl Tag for WitnessScriptTag {}
diff --git a/primitives/tests/api.rs b/primitives/tests/api.rs
index c572b8f6..bbb6eef0 100644
--- a/primitives/tests/api.rs
+++ b/primitives/tests/api.rs
@@ -19,7 +19,7 @@ use bitcoin_primitives::script::{self, ScriptHash, WScriptHash};
 use bitcoin_primitives::{
     absolute, block, merkle_tree, pow, relative, transaction, witness, OutPoint, RedeemScript,
     RedeemScriptBuf, Script, ScriptBuf, ScriptPubKey, ScriptPubKeyBuf, ScriptSig, ScriptSigBuf,
-    Sequence, Transaction, TxIn, TxOut, Txid, Witness, Wtxid,
+    Sequence, Transaction, TxIn, TxOut, Txid, Witness, WitnessScript, WitnessScriptBuf, Wtxid,
 };
 use hashes::sha256t;
 
@@ -48,12 +48,14 @@ struct Structs<'a> {
     j1: &'a RedeemScript,
     j2: &'a ScriptPubKey,
     j3: &'a ScriptSig,
+    j5: &'a WitnessScript,
     k: ScriptHash,
     l: WScriptHash,
     m: ScriptBuf,
     m1: RedeemScriptBuf,
     m2: ScriptPubKeyBuf,
     m3: ScriptSigBuf,
+    m5: WitnessScriptBuf,
     n: Sequence,
     o: Transaction,
     p: TxIn,
@@ -70,6 +72,7 @@ static SCRIPT: ScriptBuf = ScriptBuf::new();
 static REDEEM_SCRIPT: RedeemScriptBuf = RedeemScriptBuf::new();
 static SCRIPT_SIG: ScriptSigBuf = ScriptSigBuf::new();
 static SCRIPT_PUB_KEY: ScriptPubKeyBuf = ScriptPubKeyBuf::new();
+static WITNESS_SCRIPT: WitnessScriptBuf = WitnessScriptBuf::new();
 static BYTES: [u8; 32] = [0x00; 32];
 
 /// Public structs that derive common traits.
@@ -92,6 +95,7 @@ struct CommonTraits {
     m1: RedeemScriptBuf,
     m2: ScriptPubKeyBuf,
     m3: ScriptSigBuf,
+    m5: WitnessScriptBuf,
     n: Sequence,
     o: Transaction,
     p: TxIn,
@@ -123,6 +127,7 @@ struct Clone<'a> {
     m1: RedeemScriptBuf,
     m2: ScriptPubKeyBuf,
     m3: ScriptSigBuf,
+    m5: WitnessScriptBuf,
     n: Sequence,
     o: Transaction,
     p: TxIn,
@@ -155,6 +160,7 @@ struct Ord {
     m1: RedeemScriptBuf,
     m2: ScriptPubKeyBuf,
     m3: ScriptSigBuf,
+    m5: WitnessScriptBuf,
     n: Sequence,
     o: Transaction,
     p: TxIn,
@@ -175,10 +181,12 @@ struct Default {
     b1: &'static RedeemScript,
     b2: &'static ScriptPubKey,
     b3: &'static ScriptSig,
+    b5: &'static WitnessScript,
     c: ScriptBuf,
     c1: RedeemScriptBuf,
     c2: ScriptPubKeyBuf,
     c3: ScriptSigBuf,
+    c5: WitnessScriptBuf,
     d: Sequence,
     e: Witness,
 }
@@ -295,12 +303,14 @@ fn api_all_non_error_types_have_non_empty_debug() {
         REDEEM_SCRIPT.as_script();
         SCRIPT_SIG.as_script();
         SCRIPT_PUB_KEY.as_script();
+        WITNESS_SCRIPT.as_script();
         ScriptHash::from_script(&REDEEM_SCRIPT).unwrap();
-        WScriptHash::from_script(&SCRIPT).unwrap();
+        WScriptHash::from_script(&WITNESS_SCRIPT).unwrap();
         SCRIPT.clone();
         REDEEM_SCRIPT.clone();
         SCRIPT_SIG.clone();
         SCRIPT_PUB_KEY.clone();
+        WITNESS_SCRIPT.clone();
         Sequence::arbitrary(&mut u).unwrap();
         Transaction::arbitrary(&mut u).unwrap();
         TxIn::arbitrary(&mut u).unwrap();
@@ -339,10 +349,12 @@ fn regression_default() {
         b1: RedeemScript::from_bytes(&[]),
         b2: ScriptPubKey::from_bytes(&[]),
         b3: ScriptSig::from_bytes(&[]),
+        b5: WitnessScript::from_bytes(&[]),
         c: ScriptBuf::from_bytes(Vec::new()),
         c1: RedeemScriptBuf::from_bytes(Vec::new()),
         c2: ScriptPubKeyBuf::from_bytes(Vec::new()),
         c3: ScriptSigBuf::from_bytes(Vec::new()),
+        c5: WitnessScriptBuf::from_bytes(Vec::new()),
         d: Sequence::MAX,
         e: Witness::new(),
     };