diff --git a/contracts/Contribution.sol b/contracts/Contribution.sol
new file mode 100644
index 0000000..5fa52b3
--- /dev/null
+++ b/contracts/Contribution.sol
@@ -0,0 +1,92 @@
+pragma solidity ^0.4.18;
+
+import "zeppelin-solidity/contracts/token/ERC721/ERC721Token.sol";
+import './upgradeable/Upgradeable.sol';
+
+// ToDo: only load interfaces
+import './Token.sol';
+
+contract Contribution is Upgradeable, ERC721Token { 
+
+  struct Contribution {
+    address contributor;
+    uint amount;
+    bool issued;
+    uint proposalId;
+    string url;
+    uint256 claimAfterBlock;
+    bool exists;
+  }
+  string internal name_;
+  string internal symbol_;
+  
+  mapping(uint256 => string) contributionURIs;
+  
+  mapping(uint256 => address) contributionOwner;
+  mapping(address => uint256[]) ownedContributions;
+
+  mapping(uint256 => Contribution) public contributions;
+  uint256 public contributionsCount;
+
+  event ContributionAdded(uint256 id, address indexed contributor, uint256 amount);
+
+  function tokenContract() view public returns (Token) {
+    return Token(registry.getProxyFor('Token'));
+  }
+
+  function name() external view returns (string) {
+    return name_;
+  }
+
+  function symbol() external view returns (string) {
+    return symbol_;
+  }
+
+  function contributionURI(uint256 contributionId) public view returns (string) {
+    require(exists(contributionId));
+    return contributions[contributionId].url;
+  }
+
+  function ownerOf(uint256 contributionId) public view returns (address) {
+    require(exists(contributionId));
+    return contributions[contributionId].contributor;
+  }
+
+  function balanceOf(address contributor) public view returns (uint) {
+    return ownedContributions[contributor].length;
+  }
+
+  function add(uint256 amount, uint256 proposalId, address contributor, uint256 blocksToWait, string url) public {
+    uint contributionId = contributionsCount + 1;
+    var c = contributions[contributionId];
+    c.exists = true;
+    c.amount = amount;
+    c.issued = false;
+    c.proposalId = proposalId;
+    c.url = url;
+    c.contributor = contributor;
+    c.claimAfterBlock = block.number + blocksToWait;
+
+    contributionsCount++;
+   
+    contributionOwner[contributionId] = contributor;
+    ownedContributions[contributor].push(contributionId);
+
+    ContributionAdded(contributionId, contributor, amount);
+  }
+
+  function claim(uint256 contributionId) public {
+    var c = contributions[contributionId];
+    require(c.exists);
+    require(!c.issued);
+    require(block.number > c.claimAfterBlock);
+    tokenContract().mintFor(c.contributor, c.amount, contributionId);
+    c.issued = true;
+  }
+
+  function exists(uint256 contributionId) view public returns (bool) {
+    return contributions[contributionId].exists; 
+  }
+
+
+}
diff --git a/contracts/Token.sol b/contracts/Token.sol
index 9d81a9f..61ca124 100644
--- a/contracts/Token.sol
+++ b/contracts/Token.sol
@@ -17,7 +17,7 @@ contract Token is Upgradeable, BasicToken {
     decimals = 18;
   }
 
-  function mintFor(address contributorAccount, uint256 amount, uint proposalId) onlyRegistryContractFor('Operator') public {
+  function mintFor(address contributorAccount, uint256 amount, uint proposalId) onlyRegistryContractFor('Contribution') public {
     totalSupply_ = totalSupply_.add(amount);
     balances[contributorAccount] = balances[contributorAccount].add(amount); 
 
diff --git a/migrations/1528988660_contribution.js b/migrations/1528988660_contribution.js
new file mode 100644
index 0000000..f6cb6a9
--- /dev/null
+++ b/migrations/1528988660_contribution.js
@@ -0,0 +1,13 @@
+var Registry = artifacts.require('./Registry.sol');
+var Contribution = artifacts.require('./Contribution.sol');
+
+module.exports = function(deployer) {
+  deployer.deploy(Contribution).then(function(contribution) {
+    console.log('Registry address: ', Registry.address);
+    console.log('Contribution address: ', Contribution.address);
+    Registry.deployed().then(function(registry) {
+      registry.addVersion('Contribution', Contribution.address);
+      registry.createProxy('Contribution', 1);
+    });
+  });
+};