diff --git a/contracts/MemberSystem/impl/MemAggregator.sol b/contracts/MemberSystem/impl/MemAggregator.sol
new file mode 100644
index 0000000..e519cd8
--- /dev/null
+++ b/contracts/MemberSystem/impl/MemAggregator.sol
@@ -0,0 +1,57 @@
+/*
+
+    Copyright 2020 DODO ZOO.
+    SPDX-License-Identifier: Apache-2.0
+
+*/
+
+pragma solidity 0.6.9;
+pragma experimental ABIEncoderV2;
+
+import {Ownable} from "../../lib/Ownable.sol";
+import {SafeMath} from "../../lib/SafeMath.sol";
+import {DecimalMath} from "../../lib/DecimalMath.sol";
+
+interface IMemSource {
+    function getMemLevel(address user) external returns (uint256);
+}
+
+contract MemRegistry is Ownable {
+    using SafeMath for uint256;
+
+    address[] internal _VALID_MEM_SOURCE_LIST_;
+    mapping(address => bool) internal _VALID_MEM_SOURCE_;
+    mapping(address => uint256) internal _MEM_SOURCE_WEIGHT_;
+
+    function getMemLevel(address user) public returns (uint256 memLevel) {
+        for (uint8 i = 0; i < _VALID_MEM_SOURCE_LIST_.length; i++) {
+            address _source = _VALID_MEM_SOURCE_LIST_[i];
+            memLevel = memLevel.add(
+                IMemSource(_source).getMemLevel(user).mul(_MEM_SOURCE_WEIGHT_[_source])
+            );
+        }
+    }
+
+    function setMemSourceWeight(address source, uint256 weight) external onlyOwner {
+        _MEM_SOURCE_WEIGHT_[source] = weight;
+    }
+
+    function addMemSource(address source) external onlyOwner {
+        require(!_VALID_MEM_SOURCE_[source], "SOURCE_ALREADY_EXIST");
+        _VALID_MEM_SOURCE_LIST_.push(source);
+        _VALID_MEM_SOURCE_[source] = true;
+    }
+
+    function removeMemSource(address source) external onlyOwner {
+        require(_VALID_MEM_SOURCE_[source], "SOURCE_NOT_EXIST");
+        for (uint8 i = 0; i <= _VALID_MEM_SOURCE_LIST_.length - 1; i++) {
+            if (_VALID_MEM_SOURCE_LIST_[i] == source) {
+                _VALID_MEM_SOURCE_LIST_[i] = _VALID_MEM_SOURCE_LIST_[_VALID_MEM_SOURCE_LIST_
+                    .length - 1];
+                _VALID_MEM_SOURCE_LIST_.pop();
+                break;
+            }
+        }
+        _VALID_MEM_SOURCE_[source] = false;
+    }
+}
diff --git a/contracts/MemberSystem/impl/MemSourceStake.sol b/contracts/MemberSystem/impl/MemSourceStake.sol
new file mode 100644
index 0000000..6a2cb50
--- /dev/null
+++ b/contracts/MemberSystem/impl/MemSourceStake.sol
@@ -0,0 +1,85 @@
+/*
+
+    Copyright 2020 DODO ZOO.
+    SPDX-License-Identifier: Apache-2.0
+
+*/
+
+pragma solidity 0.6.9;
+pragma experimental ABIEncoderV2;
+
+import {Ownable} from "../../lib/Ownable.sol";
+import {IMemSource} from "./MemAggregator.sol";
+import {IERC20} from "../../intf/IERC20.sol";
+import {SafeMath} from "../../lib/SafeMath.sol";
+import {SafeERC20} from "../../lib/SafeERC20.sol";
+import {DecimalMath} from "../../lib/DecimalMath.sol";
+
+contract MemSourceStake is Ownable, IMemSource {
+    using SafeMath for uint256;
+    using SafeERC20 for IERC20;
+
+    address public _DODO_TOKEN_;
+    uint256 public _DODO_RESERVE_;
+    uint256 public _COLD_DOWN_DURATION_;
+
+    mapping(address => uint256) internal _STAKED_DODO_;
+    mapping(address => uint256) internal _PENDING_DODO_;
+    mapping(address => uint256) internal _EXECUTE_TIME_;
+
+    constructor(address dodoToken) public {
+        _DODO_TOKEN_ = dodoToken;
+    }
+
+    // ============ Owner Function ============
+
+    function setColdDownDuration(uint256 coldDownDuration) external onlyOwner {
+        _COLD_DOWN_DURATION_ = coldDownDuration;
+    }
+
+    // ============ DODO Function ============
+
+    function admitStakedDODO(address to) external {
+        uint256 dodoInput = IERC20(_DODO_TOKEN_).balanceOf(address(this)).sub(_DODO_RESERVE_);
+        _STAKED_DODO_[to] = _STAKED_DODO_[to].add(dodoInput);
+        _sync();
+    }
+
+    function stakeDODO(uint256 amount) external {
+        _transferDODOIn(msg.sender, amount);
+        _STAKED_DODO_[msg.sender] = _STAKED_DODO_[msg.sender].add(amount);
+        _sync();
+    }
+
+    function requestDODOWithdraw(uint256 amount) external {
+        _STAKED_DODO_[msg.sender] = _STAKED_DODO_[msg.sender].sub(amount);
+        _PENDING_DODO_[msg.sender] = _PENDING_DODO_[msg.sender].add(amount);
+        _EXECUTE_TIME_[msg.sender] = block.timestamp.add(_COLD_DOWN_DURATION_);
+    }
+
+    function withdrawDODO() external {
+        require(_EXECUTE_TIME_[msg.sender] <= block.timestamp, "WITHDRAW_COLD_DOWN");
+        _transferDODOOut(msg.sender, _PENDING_DODO_[msg.sender]);
+        _PENDING_DODO_[msg.sender] = 0;
+    }
+
+    // ============ Balance Function ============
+
+    function _transferDODOIn(address from, uint256 amount) internal {
+        IERC20(_DODO_TOKEN_).transferFrom(from, address(this), amount);
+    }
+
+    function _transferDODOOut(address to, uint256 amount) internal {
+        IERC20(_DODO_TOKEN_).transfer(to, amount);
+    }
+
+    function _sync() internal {
+        _DODO_RESERVE_ = IERC20(_DODO_TOKEN_).balanceOf(address(this));
+    }
+
+    // ============ View Function ============
+
+    function getMemLevel(address user) external override returns (uint256) {
+        return _STAKED_DODO_[user];
+    }
+}