diff --git a/zebra-chain/src/lib.rs b/zebra-chain/src/lib.rs
index 8f982899..2f895e45 100644
--- a/zebra-chain/src/lib.rs
+++ b/zebra-chain/src/lib.rs
@@ -15,7 +15,6 @@ mod merkle_tree;
 
 pub mod addresses;
 pub mod keys;
-pub mod notes;
 
 pub mod amount;
 pub mod block;
diff --git a/zebra-chain/src/notes.rs b/zebra-chain/src/notes.rs
deleted file mode 100644
index 24b15871..00000000
--- a/zebra-chain/src/notes.rs
+++ /dev/null
@@ -1,5 +0,0 @@
-//! Notes, note encryption, and nullifier types.
-
-#[cfg(test)]
-mod arbitrary;
-pub mod memo;
diff --git a/zebra-chain/src/notes/arbitrary.rs b/zebra-chain/src/notes/arbitrary.rs
deleted file mode 100644
index c562f784..00000000
--- a/zebra-chain/src/notes/arbitrary.rs
+++ /dev/null
@@ -1,19 +0,0 @@
-use crate::notes::memo::Memo;
-
-use proptest::{arbitrary::any, collection::vec, prelude::*};
-
-impl Arbitrary for Memo {
-    type Parameters = ();
-
-    fn arbitrary_with(_args: Self::Parameters) -> Self::Strategy {
-        (vec(any::<u8>(), 512))
-            .prop_map(|v| {
-                let mut bytes = [0; 512];
-                bytes.copy_from_slice(v.as_slice());
-                Memo(Box::new(bytes))
-            })
-            .boxed()
-    }
-
-    type Strategy = BoxedStrategy<Self>;
-}
diff --git a/zebra-chain/src/notes/test_vectors.rs b/zebra-chain/src/notes/test_vectors.rs
deleted file mode 100644
index 1be708b1..00000000
--- a/zebra-chain/src/notes/test_vectors.rs
+++ /dev/null
@@ -1,58 +0,0 @@
-pub const MEMO_FIELD_INVALID_UTF8_BYTES = [0xf6, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-                0x00, 0x00, 0x00, 0x00];
diff --git a/zebra-chain/src/sapling/note.rs b/zebra-chain/src/sapling/note.rs
index ad10703d..82936dc0 100644
--- a/zebra-chain/src/sapling/note.rs
+++ b/zebra-chain/src/sapling/note.rs
@@ -11,7 +11,7 @@ mod arbitrary;
 
 use crate::{
     amount::{Amount, NonNegative},
-    notes::memo::Memo,
+    transaction::Memo,
 };
 
 use super::{
diff --git a/zebra-chain/src/sprout/note.rs b/zebra-chain/src/sprout/note.rs
index bbcd532e..0dacf1f9 100644
--- a/zebra-chain/src/sprout/note.rs
+++ b/zebra-chain/src/sprout/note.rs
@@ -11,7 +11,7 @@ mod nullifiers;
 
 use crate::{
     amount::{Amount, NonNegative},
-    notes::memo::Memo,
+    transaction::Memo,
 };
 
 use super::{commitment::CommitmentRandomness, keys::PayingKey};
diff --git a/zebra-chain/src/sprout/note/arbitrary.rs b/zebra-chain/src/sprout/note/arbitrary.rs
index 1e6e02ad..e151b8a2 100644
--- a/zebra-chain/src/sprout/note/arbitrary.rs
+++ b/zebra-chain/src/sprout/note/arbitrary.rs
@@ -1,6 +1,5 @@
 use proptest::{arbitrary::any, collection::vec, prelude::*};
 
-
 impl Arbitrary for super::EncryptedCiphertext {
     type Parameters = ();
 
diff --git a/zebra-chain/src/transaction.rs b/zebra-chain/src/transaction.rs
index 41d743fb..d8d59744 100644
--- a/zebra-chain/src/transaction.rs
+++ b/zebra-chain/src/transaction.rs
@@ -5,6 +5,7 @@ use serde::{Deserialize, Serialize};
 mod hash;
 mod joinsplit;
 mod lock_time;
+mod memo;
 mod serialize;
 mod shielded_data;
 mod transparent;
@@ -15,6 +16,7 @@ mod tests;
 pub use hash::TransactionHash;
 pub use joinsplit::{JoinSplit, JoinSplitData};
 pub use lock_time::LockTime;
+pub use memo::Memo;
 pub use shielded_data::{Output, ShieldedData, Spend};
 pub use transparent::{CoinbaseData, OutPoint, TransparentInput, TransparentOutput};
 
diff --git a/zebra-chain/src/transaction/joinsplit.rs b/zebra-chain/src/transaction/joinsplit.rs
index 54ef5901..1d59834a 100644
--- a/zebra-chain/src/transaction/joinsplit.rs
+++ b/zebra-chain/src/transaction/joinsplit.rs
@@ -2,8 +2,8 @@ use serde::{Deserialize, Serialize};
 
 use crate::{
     amount::{Amount, NonNegative},
-    sprout,
     primitives::{ed25519, x25519, ZkSnarkProof},
+    sprout,
 };
 
 /// A _JoinSplit Description_, as described in [protocol specification §7.2][ps].
diff --git a/zebra-chain/src/notes/memo.rs b/zebra-chain/src/transaction/memo.rs
similarity index 98%
rename from zebra-chain/src/notes/memo.rs
rename to zebra-chain/src/transaction/memo.rs
index dec549a8..e5d0ad52 100644
--- a/zebra-chain/src/notes/memo.rs
+++ b/zebra-chain/src/transaction/memo.rs
@@ -1,6 +1,6 @@
 use std::{cmp, convert::TryFrom, fmt};
 
-/// A 512-byte _Memo_ field associated with a note, as described in
+/// A 512-byte (plaintext) memo associated with a note, as described in
 /// [protocol specification §5.5][ps].
 ///
 /// The _Memo_ field of a note is a plaintext type; the parent note is
diff --git a/zebra-chain/src/transaction/tests/arbitrary.rs b/zebra-chain/src/transaction/tests/arbitrary.rs
index d22c39e4..0d45b58c 100644
--- a/zebra-chain/src/transaction/tests/arbitrary.rs
+++ b/zebra-chain/src/transaction/tests/arbitrary.rs
@@ -6,12 +6,12 @@ use crate::{
     amount::{Amount, NonNegative},
     block::BlockHeight,
     primitives::{Bctv14Proof, Groth16Proof, Script, ZkSnarkProof},
-    sapling,
-    sprout,
-    transaction::{
-        CoinbaseData, JoinSplit, JoinSplitData, LockTime, OutPoint, Output, ShieldedData, Spend,
-        Transaction, TransparentInput, TransparentOutput,
-    },
+    sapling, sprout,
+};
+
+use super::super::{
+    CoinbaseData, JoinSplit, JoinSplitData, LockTime, Memo, OutPoint, Output, ShieldedData, Spend,
+    Transaction, TransparentInput, TransparentOutput,
 };
 
 impl Transaction {
@@ -100,6 +100,22 @@ impl Transaction {
     }
 }
 
+impl Arbitrary for Memo {
+    type Parameters = ();
+
+    fn arbitrary_with(_args: Self::Parameters) -> Self::Strategy {
+        (vec(any::<u8>(), 512))
+            .prop_map(|v| {
+                let mut bytes = [0; 512];
+                bytes.copy_from_slice(v.as_slice());
+                Memo(Box::new(bytes))
+            })
+            .boxed()
+    }
+
+    type Strategy = BoxedStrategy<Self>;
+}
+
 impl Arbitrary for LockTime {
     type Parameters = ();