diff --git a/contracts/UFragmentsPolicy.sol b/contracts/UFragmentsPolicy.sol
index 38d37ea4..67923fa4 100644
--- a/contracts/UFragmentsPolicy.sol
+++ b/contracts/UFragmentsPolicy.sol
@@ -212,14 +212,14 @@ contract UFragmentsPolicy is Ownable {
 
     /**
      * @notice A multi-chain AMPL interface method. The Ampleforth monetary policy contract
-     *         on the base-chain and XCAmpleController contracts on the satellite-chains
+     *         on the base-chain and XC-AmpleController contracts on the satellite-chains
      *         implement this method. It atomically returns two values:
      *         what the current contract believes to be,
      *         the globalAmpleforthEpoch and globalAMPLSupply.
      * @return globalAmpleforthEpoch The current epoch number.
      * @return globalAMPLSupply The total supply at the current epoch.
      */
-    function getGlobalAmpleforthEpochAndAMPLSupply() external view returns (uint256, uint256) {
+    function globalAmpleforthEpochAndAMPLSupply() external view returns (uint256, uint256) {
         return (epoch, uFrags.totalSupply());
     }
 
diff --git a/contracts/interfaces/IAMPL.sol b/contracts/interfaces/IAMPL.sol
new file mode 100644
index 00000000..ba28c15f
--- /dev/null
+++ b/contracts/interfaces/IAMPL.sol
@@ -0,0 +1,49 @@
+pragma solidity 0.4.24;
+
+// Public interface definition for the AMPL - ERC20 token on Ethereum (the base-chain)
+interface IAMPL {
+    // ERC20
+    function totalSupply() external view returns (uint256);
+
+    function balanceOf(address who) external view returns (uint256);
+
+    function allowance(address owner_, address spender) external view returns (uint256);
+
+    function transfer(address to, uint256 value) external returns (bool);
+
+    function approve(address spender, uint256 value) external returns (bool);
+
+    function increaseAllowance(address spender, uint256 addedValue) external returns (bool);
+
+    function decreaseAllowance(address spender, uint256 subtractedValue) external returns (bool);
+
+    function transferFrom(
+        address from,
+        address to,
+        uint256 value
+    ) external returns (bool);
+
+    // EIP-2612
+    function permit(
+        address owner,
+        address spender,
+        uint256 value,
+        uint256 deadline,
+        uint8 v,
+        bytes32 r,
+        bytes32 s
+    ) external;
+
+    function nonces(address owner) external view returns (uint256);
+
+    function DOMAIN_SEPARATOR() external view returns (bytes32);
+
+    // Elastic token interface
+    function scaledBalanceOf(address who) external view returns (uint256);
+
+    function scaledTotalSupply() external view returns (uint256);
+
+    function transferAll(address to) external returns (bool);
+
+    function transferAllFrom(address from, address to) external returns (bool);
+}
diff --git a/contracts/interfaces/IAmpleforth.sol b/contracts/interfaces/IAmpleforth.sol
new file mode 100644
index 00000000..b63cc6b3
--- /dev/null
+++ b/contracts/interfaces/IAmpleforth.sol
@@ -0,0 +1,12 @@
+pragma solidity 0.4.24;
+
+// Public interface definition for the Ampleforth supply policy on Ethereum (the base-chain)
+interface IAmpleforth {
+    function epoch() external view returns (uint256);
+
+    function lastRebaseTimestampSec() external view returns (uint256);
+
+    function inRebaseWindow() external view returns (bool);
+
+    function globalAmpleforthEpochAndAMPLSupply() external view returns (uint256, uint256);
+}
diff --git a/contracts/interfaces/IOrchestrator.sol b/contracts/interfaces/IOrchestrator.sol
new file mode 100644
index 00000000..c1184013
--- /dev/null
+++ b/contracts/interfaces/IOrchestrator.sol
@@ -0,0 +1,6 @@
+pragma solidity 0.4.24;
+
+// Public interface definition for the Ampleforth Orchestrator on Ethereum (the base-chain)
+interface IOrchestrator {
+    function rebase() external;
+}
diff --git a/test/unit/UFragmentsPolicy.ts b/test/unit/UFragmentsPolicy.ts
index 149f3c6a..4f6af3c6 100644
--- a/test/unit/UFragmentsPolicy.ts
+++ b/test/unit/UFragmentsPolicy.ts
@@ -164,8 +164,8 @@ describe('UFragmentsPolicy:initialize', async function () {
     it('epoch', async function () {
       expect(await uFragmentsPolicy.epoch()).to.eq(0)
     })
-    it('getGlobalAmpleforthEpochAndAMPLSupply', async function () {
-      const r = await uFragmentsPolicy.getGlobalAmpleforthEpochAndAMPLSupply()
+    it('globalAmpleforthEpochAndAMPLSupply', async function () {
+      const r = await uFragmentsPolicy.globalAmpleforthEpochAndAMPLSupply()
       expect(r[0]).to.eq(0)
       expect(r[1]).to.eq(0)
     })
@@ -833,9 +833,9 @@ describe('UFragmentsPolicy:Rebase', async function () {
       expect(await uFragmentsPolicy.epoch()).to.eq(prevEpoch.add(1))
     })
 
-    it('should update getGlobalAmpleforthEpochAndAMPLSupply', async function () {
+    it('should update globalAmpleforthEpochAndAMPLSupply', async function () {
       await uFragmentsPolicy.connect(orchestrator).rebase()
-      const r = await uFragmentsPolicy.getGlobalAmpleforthEpochAndAMPLSupply()
+      const r = await uFragmentsPolicy.globalAmpleforthEpochAndAMPLSupply()
       expect(r[0]).to.eq(prevEpoch.add(1))
       expect(r[1]).to.eq('1010')
     })