diff --git a/contracts/components/IRiskpool.sol b/contracts/components/IRiskpool.sol
index c54dd19..97f2060 100644
--- a/contracts/components/IRiskpool.sol
+++ b/contracts/components/IRiskpool.sol
@@ -21,6 +21,12 @@ interface IRiskpool is IComponent {
     event LogRiskpoolBalanceDecreased(bytes32 processId, uint256 amount, uint256 newBalance);
 
     function createBundle(bytes calldata filter, uint256 initialAmount) external returns(uint256 bundleId);
+    function fundBundle(uint256 bundleId, uint256 amount) external;
+    function defundBundle(uint256 bundleId, uint256 amount) external;
+
+    function lockBundle(uint256 bundleId) external;
+    function unlockBundle(uint256 bundleId) external;
+    function closeBundle(uint256 bundleId) external;
 
     function collateralizePolicy(bytes32 processId) external returns(bool isSecured);
     function expirePolicy(bytes32 processId) external;
diff --git a/contracts/components/Riskpool.sol b/contracts/components/Riskpool.sol
index e9f2f5f..b4e4a18 100644
--- a/contracts/components/Riskpool.sol
+++ b/contracts/components/Riskpool.sol
@@ -10,6 +10,8 @@ import "../modules/IPolicy.sol";
 import "../services/IInstanceService.sol";
 import "../services/IRiskpoolService.sol";
 
+import "@openzeppelin/contracts/token/ERC721/IERC721.sol";
+
 // TODO consider to move bunlde per riskpool book keeping to bundle controller
 abstract contract Riskpool is 
     IRiskpool, 
@@ -24,6 +26,7 @@ abstract contract Riskpool is
 
     IInstanceService internal _instanceService; 
     IRiskpoolService internal _riskpoolService;
+    IERC721 internal _bundleToken;
     
     // keep track of bundles associated with this riskpool
     uint256 [] internal _bundleIds;
@@ -42,6 +45,17 @@ abstract contract Riskpool is
         _;
     }
 
+    modifier onlyBundleOwner(uint256 bundleId) {
+        IBundle.Bundle memory bundle = _instanceService.getBundle(bundleId);
+        address bundleOwner = _bundleToken.ownerOf(bundle.tokenId);
+
+        require(
+            _msgSender() == bundleOwner,
+            "ERROR:BUC-001:NOT_BUNDLE_OWNER"
+        );
+        _;
+    }
+
     constructor(
         bytes32 name,
         uint256 collateralization,
@@ -58,6 +72,7 @@ abstract contract Riskpool is
 
         _instanceService = IInstanceService(_getContractAddress("InstanceService")); 
         _riskpoolService = IRiskpoolService(_getContractAddress("RiskpoolService"));
+        _bundleToken = _instanceService.getBundleToken();
     }
 
     // TODO decide on authz for bundle creation
@@ -81,6 +96,40 @@ abstract contract Riskpool is
         emit LogRiskpoolBundleCreated(bundleId, initialAmount);
     }
 
+    function fundBundle(uint256 bundleId, uint256 amount) 
+        external override
+        onlyBundleOwner(bundleId)
+    {
+        _riskpoolService.fundBundle(bundleId, amount);
+    }
+
+    function defundBundle(uint256 bundleId, uint256 amount)
+        external override
+        onlyBundleOwner(bundleId)
+    {
+        _riskpoolService.defundBundle(bundleId, amount);
+    }
+
+    function lockBundle(uint256 bundleId)
+        external override
+        onlyBundleOwner(bundleId)
+    {
+        _riskpoolService.lockBundle(bundleId);
+    }
+
+    function unlockBundle(uint256 bundleId)
+        external override
+        onlyBundleOwner(bundleId)
+    {
+        _riskpoolService.unlockBundle(bundleId);
+    }
+
+    function closeBundle(uint256 bundleId)
+        external override
+        onlyBundleOwner(bundleId)
+    {
+        _riskpoolService.closeBundle(bundleId);
+    }
 
     function collateralizePolicy(bytes32 processId) 
         external override
diff --git a/contracts/modules/IBundle.sol b/contracts/modules/IBundle.sol
index f456eff..92f07c2 100644
--- a/contracts/modules/IBundle.sol
+++ b/contracts/modules/IBundle.sol
@@ -40,13 +40,15 @@ interface IBundle {
 
     function create(address owner_, uint256 riskpoolId_, bytes calldata filter_, uint256 amount_) external returns(uint256 bundleId);
     function fund(uint256 bundleId, uint256 amount) external;
-    function withdraw(uint256 bundleId, uint256 amount) external;
+    function defund(uint256 bundleId, uint256 amount) external;
 
     function lock(uint256 bundleId) external;
     function unlock(uint256 bundleId) external;
     function close(uint256 bundleId) external;
 
     function collateralizePolicy(uint256 bundleId, bytes32 processId, uint256 collateralAmount) external;
-    function addPremiumToBalance(uint256 bundleId, bytes32 processId, uint256 premiumAmount) external;
     function expirePolicy(uint256 bundleId, bytes32 processId) external returns(uint256 collateralAmount);
+
+    function increaseBalance(uint256 bundleId, bytes32 processId, uint256 amount) external;
+    function decreaseBalance(uint256 bundleId, bytes32 processId, uint256 amount) external;
 }
diff --git a/contracts/modules/IPool.sol b/contracts/modules/IPool.sol
index eb950f6..5ced7e6 100644
--- a/contracts/modules/IPool.sol
+++ b/contracts/modules/IPool.sol
@@ -9,4 +9,7 @@ interface IPool {
     function setRiskpoolForProduct(uint256 productId, uint256 riskpoolId) external;
     function underwrite(bytes32 processId) external returns(bool success);
     function expire(bytes32 processId) external; 
+
+    function increaseBalance(bytes32 processId, uint256 amount) external;
+    function decreaseBalance(bytes32 processId, uint256 amount) external;
 }
diff --git a/contracts/modules/ITreasury.sol b/contracts/modules/ITreasury.sol
index 3c2ee10..3b2ce5f 100644
--- a/contracts/modules/ITreasury.sol
+++ b/contracts/modules/ITreasury.sol
@@ -56,6 +56,12 @@ interface ITreasury {
             uint256 netCapitalAmount
         );
 
+    function processWithdrawl(uint256 bundleId, uint256 amount) external
+        returns(
+            bool success,
+            uint256 netAmount
+        );
+
     function getComponentToken(uint256 componentId) external view returns(IERC20 token);
     function getFeeSpecification(uint256 componentId) external view returns(FeeSpecification memory feeSpecification);
 
diff --git a/contracts/services/IInstanceService.sol b/contracts/services/IInstanceService.sol
index 16451b1..08cd85d 100644
--- a/contracts/services/IInstanceService.sol
+++ b/contracts/services/IInstanceService.sol
@@ -10,6 +10,7 @@ import "./IProductService.sol";
 import "./IRiskpoolService.sol";
 
 import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+import "@openzeppelin/contracts/token/ERC721/IERC721.sol";
 
 interface IInstanceService {
 
@@ -30,6 +31,7 @@ interface IInstanceService {
     function hasRole(bytes32 role, address principal) external view returns (bool roleIsAssigned);    
 
     // bundles
+    function getBundleToken() external view returns(IERC721 token);
     function bundles() external view returns(uint256 numberOfBundles);
     function getBundle(uint256 bundleId) external view returns(IBundle.Bundle memory bundle);
 
diff --git a/contracts/services/IRiskpoolService.sol b/contracts/services/IRiskpoolService.sol
index f9dd9c5..b1ddd24 100644
--- a/contracts/services/IRiskpoolService.sol
+++ b/contracts/services/IRiskpoolService.sol
@@ -4,6 +4,12 @@ pragma solidity ^0.8.0;
 interface IRiskpoolService {
 
     function createBundle(address owner_, bytes calldata filter_, uint256 amount_) external returns(uint256 bundleId);
+    function fundBundle(uint256 bundleId, uint256 amount) external;
+    function defundBundle(uint256 bundleId, uint256 amount) external;
+
+    function lockBundle(uint256 bundleId) external;
+    function unlockBundle(uint256 bundleId) external;
+    function closeBundle(uint256 bundleId) external;
 
     function collateralizePolicy(uint256 bundleId, bytes32 processId, uint256 collateralAmount) external;
     function expirePolicy(uint256 bundleId, bytes32 processId) external returns(uint256 collateralAmount);