diff --git a/Cargo.lock b/Cargo.lock
index f18e2cb345..cf8c7bbbe9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2290,6 +2290,7 @@ dependencies = [
  "chrono 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "generic-array 0.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "hex 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "ring 0.13.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.88 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/sdk/Cargo.toml b/sdk/Cargo.toml
index 42b86ef024..459d172525 100644
--- a/sdk/Cargo.toml
+++ b/sdk/Cargo.toml
@@ -15,6 +15,7 @@ hex = "0.3.2"
 byteorder = "1.2.1"
 chrono = { version = "0.4.0", features = ["serde"] }
 generic-array = { version = "0.12.0", default-features = false, features = ["serde"] }
+itertools = "0.8.0"
 log = "0.4.2"
 ring = "0.13.2"
 sha2 = "0.8.0"
diff --git a/sdk/src/budget_instruction.rs b/sdk/src/budget_instruction.rs
index 3a6ea29971..accec702eb 100644
--- a/sdk/src/budget_instruction.rs
+++ b/sdk/src/budget_instruction.rs
@@ -1,4 +1,7 @@
 use crate::budget_expr::BudgetExpr;
+use crate::budget_program;
+use crate::pubkey::Pubkey;
+use crate::transaction_builder::BuilderInstruction;
 use chrono::prelude::{DateTime, Utc};
 
 /// A smart contract.
@@ -22,3 +25,13 @@ pub enum Instruction {
     /// signed by the containing transaction's `Pubkey`.
     ApplySignature,
 }
+
+impl Instruction {
+    pub fn new_budget(contract: Pubkey, expr: BudgetExpr) -> BuilderInstruction {
+        BuilderInstruction::new(
+            budget_program::id(),
+            &Instruction::NewBudget(expr),
+            vec![(contract, false)],
+        )
+    }
+}
diff --git a/sdk/src/budget_transaction.rs b/sdk/src/budget_transaction.rs
index 3524c01654..f393e3122a 100644
--- a/sdk/src/budget_transaction.rs
+++ b/sdk/src/budget_transaction.rs
@@ -4,12 +4,11 @@ use crate::budget_expr::{BudgetExpr, Condition};
 use crate::budget_instruction::Instruction;
 use crate::budget_program;
 use crate::hash::Hash;
-use crate::payment_plan::Payment;
 use crate::pubkey::Pubkey;
 use crate::signature::{Keypair, KeypairUtil};
 use crate::system_instruction::SystemInstruction;
-use crate::system_program;
-use crate::transaction::{self, Transaction};
+use crate::transaction::Transaction;
+use crate::transaction_builder::TransactionBuilder;
 use bincode::deserialize;
 use chrono::prelude::*;
 
@@ -25,31 +24,12 @@ impl BudgetTransaction {
         fee: u64,
     ) -> Transaction {
         let contract = Keypair::new().pubkey();
-        let keys = vec![from_keypair.pubkey(), contract];
-
-        let system_instruction = SystemInstruction::Move { tokens };
-
-        let payment = Payment {
-            tokens: tokens - fee,
-            to,
-        };
-        let budget_instruction = Instruction::NewBudget(BudgetExpr::Pay(payment));
-
-        let program_ids = vec![system_program::id(), budget_program::id()];
-
-        let instructions = vec![
-            transaction::Instruction::new(0, &system_instruction, vec![0, 1]),
-            transaction::Instruction::new(1, &budget_instruction, vec![1]),
-        ];
-
-        Transaction::new_with_instructions(
-            &[from_keypair],
-            &keys,
-            last_id,
-            fee,
-            program_ids,
-            instructions,
-        )
+        let from = from_keypair.pubkey();
+        let payment = BudgetExpr::new_payment(tokens - fee, to);
+        TransactionBuilder::new(fee)
+            .push(SystemInstruction::new_move(from, contract, tokens))
+            .push(Instruction::new_budget(contract, payment))
+            .sign(&[from_keypair], last_id)
     }
 
     /// Create and sign a new Transaction. Used for unit-testing.
@@ -230,23 +210,13 @@ mod tests {
 
     #[test]
     fn test_serialize_claim() {
-        let expr = BudgetExpr::Pay(Payment {
-            tokens: 0,
-            to: Pubkey::default(),
-        });
-        let instruction = Instruction::NewBudget(expr);
-        let instructions = vec![transaction::Instruction::new(0, &instruction, vec![])];
-        let claim0 = Transaction {
-            account_keys: vec![],
-            last_id: Hash::default(),
-            signatures: vec![],
-            program_ids: vec![],
-            instructions,
-            fee: 0,
-        };
-        let buf = serialize(&claim0).unwrap();
-        let claim1: Transaction = deserialize(&buf).unwrap();
-        assert_eq!(claim1, claim0);
+        let zero = Hash::default();
+        let keypair0 = Keypair::new();
+        let pubkey1 = Keypair::new().pubkey();
+        let tx0 = BudgetTransaction::new_payment(&keypair0, pubkey1, 1, zero, 1);
+        let buf = serialize(&tx0).unwrap();
+        let tx1: Transaction = deserialize(&buf).unwrap();
+        assert_eq!(tx1, tx0);
     }
 
     #[test]
diff --git a/sdk/src/lib.rs b/sdk/src/lib.rs
index 3f217c9e4a..27c3a7452d 100644
--- a/sdk/src/lib.rs
+++ b/sdk/src/lib.rs
@@ -22,6 +22,7 @@ pub mod system_transaction;
 pub mod timing;
 pub mod token_program;
 pub mod transaction;
+pub mod transaction_builder;
 pub mod vote_program;
 pub mod vote_transaction;
 
diff --git a/sdk/src/system_instruction.rs b/sdk/src/system_instruction.rs
index 5e7f56d5e3..e66c0a4f1b 100644
--- a/sdk/src/system_instruction.rs
+++ b/sdk/src/system_instruction.rs
@@ -1,4 +1,6 @@
 use crate::pubkey::Pubkey;
+use crate::system_program;
+use crate::transaction_builder::BuilderInstruction;
 
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq)]
 pub enum SystemInstruction {
@@ -21,3 +23,13 @@ pub enum SystemInstruction {
     /// * Transaction::keys[1] - destination
     Move { tokens: u64 },
 }
+
+impl SystemInstruction {
+    pub fn new_move(from_id: Pubkey, to_id: Pubkey, tokens: u64) -> BuilderInstruction {
+        BuilderInstruction::new(
+            system_program::id(),
+            &SystemInstruction::Move { tokens },
+            vec![(from_id, true), (to_id, false)],
+        )
+    }
+}
diff --git a/sdk/src/transaction_builder.rs b/sdk/src/transaction_builder.rs
new file mode 100644
index 0000000000..e2c3e09631
--- /dev/null
+++ b/sdk/src/transaction_builder.rs
@@ -0,0 +1,246 @@
+//! A library for composing transactions.
+
+use crate::hash::Hash;
+use crate::pubkey::Pubkey;
+use crate::signature::KeypairUtil;
+use crate::transaction::{Instruction, Transaction};
+use itertools::Itertools;
+
+pub type BuilderInstruction = Instruction<Pubkey, (Pubkey, bool)>;
+
+fn position(keys: &[Pubkey], key: Pubkey) -> u8 {
+    keys.iter().position(|&k| k == key).unwrap() as u8
+}
+
+fn create_indexed_instruction(
+    ix: &Instruction<Pubkey, (Pubkey, bool)>,
+    keys: &[Pubkey],
+    program_ids: &[Pubkey],
+) -> Instruction<u8, u8> {
+    let accounts: Vec<_> = ix
+        .accounts
+        .iter()
+        .map(|&(k, _)| position(keys, k))
+        .collect();
+    Instruction {
+        program_ids_index: position(program_ids, ix.program_ids_index),
+        userdata: ix.userdata.clone(),
+        accounts,
+    }
+}
+
+/// A utility for constructing transactions
+#[derive(Default)]
+pub struct TransactionBuilder {
+    fee: u64,
+    instructions: Vec<BuilderInstruction>,
+}
+
+impl TransactionBuilder {
+    /// Create a new TransactionBuilder.
+    pub fn new(fee: u64) -> Self {
+        Self {
+            fee,
+            instructions: vec![],
+        }
+    }
+
+    /// Add an instruction.
+    pub fn push(&mut self, instruction: BuilderInstruction) -> &mut Self {
+        self.instructions.push(instruction);
+        self
+    }
+
+    /// Return pubkeys referenced by all instructions, with the ones needing signatures first.
+    /// No duplicates and order is preserved.
+    fn keys(&self) -> Vec<Pubkey> {
+        let mut key_and_signed: Vec<_> = self
+            .instructions
+            .iter()
+            .flat_map(|ix| ix.accounts.iter())
+            .collect();
+        key_and_signed.sort_by(|x, y| y.1.cmp(&x.1));
+        key_and_signed.into_iter().map(|x| x.0).unique().collect()
+    }
+
+    /// Return program ids referenced by all instructions.  No duplicates and order is preserved.
+    fn program_ids(&self) -> Vec<Pubkey> {
+        self.instructions
+            .iter()
+            .map(|ix| ix.program_ids_index)
+            .unique()
+            .collect()
+    }
+
+    /// Return the instructions, but indexing lists of keys and program ids.
+    fn instructions(&self, keys: &[Pubkey], program_ids: &[Pubkey]) -> Vec<Instruction<u8, u8>> {
+        self.instructions
+            .iter()
+            .map(|ix| create_indexed_instruction(ix, keys, program_ids))
+            .collect()
+    }
+
+    /// Return a signed transaction.
+    pub fn sign<T: KeypairUtil>(&self, keypairs: &[&T], last_id: Hash) -> Transaction {
+        let keys = self.keys();
+        let program_ids = self.program_ids();
+        let instructions = self.instructions(&keys, &program_ids);
+        for (i, keypair) in keypairs.iter().enumerate() {
+            assert_eq!(keypair.pubkey(), keys[i], "keypair-pubkey mismatch");
+        }
+        let unsigned_keys = &keys[keypairs.len()..];
+        Transaction::new_with_instructions(
+            keypairs,
+            unsigned_keys,
+            last_id,
+            self.fee,
+            program_ids,
+            instructions,
+        )
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::signature::{Keypair, KeypairUtil};
+
+    #[test]
+    fn test_transaction_builder_unique_program_ids() {
+        let program_id0 = Pubkey::default();
+        let program_ids = TransactionBuilder::default()
+            .push(Instruction::new(program_id0, &0, vec![]))
+            .push(Instruction::new(program_id0, &0, vec![]))
+            .program_ids();
+        assert_eq!(program_ids, vec![program_id0]);
+    }
+
+    #[test]
+    fn test_transaction_builder_unique_program_ids_not_adjacent() {
+        let program_id0 = Pubkey::default();
+        let program_id1 = Keypair::new().pubkey();
+        let program_ids = TransactionBuilder::default()
+            .push(Instruction::new(program_id0, &0, vec![]))
+            .push(Instruction::new(program_id1, &0, vec![]))
+            .push(Instruction::new(program_id0, &0, vec![]))
+            .program_ids();
+        assert_eq!(program_ids, vec![program_id0, program_id1]);
+    }
+
+    #[test]
+    fn test_transaction_builder_unique_program_ids_order_preserved() {
+        let program_id0 = Keypair::new().pubkey();
+        let program_id1 = Pubkey::default(); // Key less than program_id0
+        let program_ids = TransactionBuilder::default()
+            .push(Instruction::new(program_id0, &0, vec![]))
+            .push(Instruction::new(program_id1, &0, vec![]))
+            .push(Instruction::new(program_id0, &0, vec![]))
+            .program_ids();
+        assert_eq!(program_ids, vec![program_id0, program_id1]);
+    }
+
+    #[test]
+    fn test_transaction_builder_unique_keys_both_signed() {
+        let program_id = Pubkey::default();
+        let id0 = Pubkey::default();
+        let keys = TransactionBuilder::default()
+            .push(Instruction::new(program_id, &0, vec![(id0, true)]))
+            .push(Instruction::new(program_id, &0, vec![(id0, true)]))
+            .keys();
+        assert_eq!(keys, vec![id0]);
+    }
+
+    #[test]
+    fn test_transaction_builder_unique_keys_one_signed() {
+        let program_id = Pubkey::default();
+        let id0 = Pubkey::default();
+        let keys = TransactionBuilder::default()
+            .push(Instruction::new(program_id, &0, vec![(id0, false)]))
+            .push(Instruction::new(program_id, &0, vec![(id0, true)]))
+            .keys();
+        assert_eq!(keys, vec![id0]);
+    }
+
+    #[test]
+    fn test_transaction_builder_unique_keys_order_preserved() {
+        let program_id = Pubkey::default();
+        let id0 = Keypair::new().pubkey();
+        let id1 = Pubkey::default(); // Key less than id0
+        let keys = TransactionBuilder::default()
+            .push(Instruction::new(program_id, &0, vec![(id0, false)]))
+            .push(Instruction::new(program_id, &0, vec![(id1, false)]))
+            .keys();
+        assert_eq!(keys, vec![id0, id1]);
+    }
+
+    #[test]
+    fn test_transaction_builder_unique_keys_not_adjacent() {
+        let program_id = Pubkey::default();
+        let id0 = Pubkey::default();
+        let id1 = Keypair::new().pubkey();
+        let keys = TransactionBuilder::default()
+            .push(Instruction::new(program_id, &0, vec![(id0, false)]))
+            .push(Instruction::new(program_id, &0, vec![(id1, false)]))
+            .push(Instruction::new(program_id, &0, vec![(id0, true)]))
+            .keys();
+        assert_eq!(keys, vec![id0, id1]);
+    }
+
+    #[test]
+    fn test_transaction_builder_signed_keys_first() {
+        let program_id = Pubkey::default();
+        let id0 = Pubkey::default();
+        let id1 = Keypair::new().pubkey();
+        let keys = TransactionBuilder::default()
+            .push(Instruction::new(program_id, &0, vec![(id0, false)]))
+            .push(Instruction::new(program_id, &0, vec![(id1, true)]))
+            .keys();
+        assert_eq!(keys, vec![id1, id0]);
+    }
+
+    #[test]
+    #[should_panic]
+    fn test_transaction_builder_missing_key() {
+        let keypair = Keypair::new();
+        TransactionBuilder::default().sign(&[&keypair], Hash::default());
+    }
+
+    #[test]
+    #[should_panic]
+    fn test_transaction_builder_wrong_key() {
+        let program_id = Pubkey::default();
+        let keypair0 = Keypair::new();
+        let wrong_id = Pubkey::default();
+        TransactionBuilder::default()
+            .push(Instruction::new(program_id, &0, vec![(wrong_id, true)]))
+            .sign(&[&keypair0], Hash::default());
+    }
+
+    #[test]
+    fn test_transaction_builder_correct_key() {
+        let program_id = Pubkey::default();
+        let keypair0 = Keypair::new();
+        let id0 = keypair0.pubkey();
+        let tx = TransactionBuilder::default()
+            .push(Instruction::new(program_id, &0, vec![(id0, true)]))
+            .sign(&[&keypair0], Hash::default());
+        assert_eq!(tx.instructions[0], Instruction::new(0, &0, vec![0]));
+    }
+
+    #[test]
+    fn test_transaction_builder_kitchen_sink() {
+        let program_id0 = Pubkey::default();
+        let program_id1 = Keypair::new().pubkey();
+        let id0 = Pubkey::default();
+        let keypair1 = Keypair::new();
+        let id1 = keypair1.pubkey();
+        let tx = TransactionBuilder::default()
+            .push(Instruction::new(program_id0, &0, vec![(id0, false)]))
+            .push(Instruction::new(program_id1, &0, vec![(id1, true)]))
+            .push(Instruction::new(program_id0, &0, vec![(id1, false)]))
+            .sign(&[&keypair1], Hash::default());
+        assert_eq!(tx.instructions[0], Instruction::new(0, &0, vec![1]));
+        assert_eq!(tx.instructions[1], Instruction::new(1, &0, vec![0]));
+        assert_eq!(tx.instructions[2], Instruction::new(0, &0, vec![0]));
+    }
+}