diff --git a/src/LockManager.sol b/src/LockManager.sol
index a5673e1..d599461 100644
--- a/src/LockManager.sol
+++ b/src/LockManager.sol
@@ -52,6 +52,12 @@ contract LockManager is ILockManager, DaoAuthorizable {
     /// @notice Raised when attempting to unlock while active votes are cast in strict mode
     error LocksStillActive();
 
+    /// @notice Thrown when trying to set an invalid contract as the plugin
+    error InvalidPlugin();
+
+    /// @notice Thrown when trying to define the address of the plugin after it already was
+    error CannotUpdatePlugin();
+
     constructor(IDAO _dao, LockManagerSettings memory _settings, IERC20 _token, IERC20 _underlyingToken)
         DaoAuthorizable(_dao)
     {
@@ -134,6 +140,8 @@ contract LockManager is ILockManager, DaoAuthorizable {
     function setPluginAddress(ILockToVote _plugin) public auth(UPDATE_SETTINGS_PERMISSION_ID) {
         if (!IERC165(address(_plugin)).supportsInterface(type(ILockToVote).interfaceId)) {
             revert InvalidPlugin();
+        } else if (address(plugin) != address(0)) {
+            revert CannotUpdatePlugin();
         }
 
         plugin = _plugin;
diff --git a/src/interfaces/ILockManager.sol b/src/interfaces/ILockManager.sol
index fa8cf99..a790500 100644
--- a/src/interfaces/ILockManager.sol
+++ b/src/interfaces/ILockManager.sol
@@ -67,7 +67,4 @@ interface ILockManager {
 
     /// @notice Defines the given plugin address as the target for voting
     function setPluginAddress(ILockToVote _plugin) external;
-
-    /// @notice Thrown then trying to set an invalid contract as the plugin
-    error InvalidPlugin();
 }
diff --git a/test/LockManager.t.sol b/test/LockManager.t.sol
index 65f9960..421dec1 100644
--- a/test/LockManager.t.sol
+++ b/test/LockManager.t.sol
@@ -27,6 +27,8 @@ contract LockManagerTest is AragonTest {
         )
     );
 
+    error InvalidUnlockMode();
+
     function setUp() public {
         vm.startPrank(alice);
         vm.warp(1 days);
@@ -43,33 +45,94 @@ contract LockManagerTest is AragonTest {
 
     function test_RevertWhen_ConstructorHasInvalidUnlockMode() external givenDeployingTheContract {
         // It Should revert
-        vm.skip(true);
+        vm.expectRevert();
+        new LockManager(
+            IDAO(address(0)), LockManagerSettings(UnlockMode(uint8(2))), IERC20(address(0)), IERC20(address(0))
+        );
+
+        vm.expectRevert();
+        new LockManager(
+            IDAO(address(0)), LockManagerSettings(UnlockMode(uint8(0))), IERC20(address(0)), IERC20(address(0))
+        );
+
+        // OK
+        new LockManager(
+            IDAO(address(0)), LockManagerSettings(UnlockMode.STRICT), IERC20(address(0)), IERC20(address(0))
+        );
+        new LockManager(IDAO(address(0)), LockManagerSettings(UnlockMode.EARLY), IERC20(address(0)), IERC20(address(0)));
     }
 
     function test_WhenConstructorWithValidParams() external givenDeployingTheContract {
         // It Registers the DAO address
         // It Stores the given settings
-        // It Stores the given plugin and token addresses
-        vm.skip(true);
-    }
-
-    modifier whenCallingUpdateSettings() {
+        // It Stores the given token addresses
+
+        // 1
+        lockManager = new LockManager(
+            IDAO(address(1234)), LockManagerSettings(UnlockMode.STRICT), IERC20(address(2345)), IERC20(address(3456))
+        );
+        assertEq(address(lockManager.dao()), address(1234));
+        assertEq(address(lockManager.token()), address(2345));
+        assertEq(address(lockManager.underlyingToken()), address(3456));
+
+        // 2
+        lockManager = new LockManager(
+            IDAO(address(5555)), LockManagerSettings(UnlockMode.EARLY), IERC20(address(6666)), IERC20(address(7777))
+        );
+        assertEq(address(lockManager.dao()), address(5555));
+        assertEq(address(lockManager.token()), address(6666));
+        assertEq(address(lockManager.underlyingToken()), address(7777));
+    }
+
+    modifier whenCallingSetPluginAddress() {
         _;
     }
 
-    function test_RevertWhen_UpdateSettingsWithoutThePermission() external whenCallingUpdateSettings {
+    function test_RevertWhen_SetPluginAddressWithoutThePermission() external whenCallingSetPluginAddress {
         // It should revert
-        vm.skip(true);
-    }
 
-    function test_WhenUpdateSettingsWithThePermission() external whenCallingUpdateSettings {
-        // It should update the mode
-        vm.skip(true);
+        (, LockToVotePlugin plugin2,,,) = builder.build();
+        (, LockToVotePlugin plugin3,,,) = builder.build();
+
+        lockManager = new LockManager(dao, LockManagerSettings(UnlockMode.STRICT), lockableToken, underlyingToken);
+
+        // 1
+        vm.expectRevert();
+        lockManager.setPluginAddress(plugin2);
+
+        // 2
+        vm.expectRevert();
+        lockManager.setPluginAddress(plugin3);
+
+        // OK
+
+        dao.grant(address(lockManager), alice, lockManager.UPDATE_SETTINGS_PERMISSION_ID());
+        lockManager.setPluginAddress(plugin2);
+
+        // OK 2
+
+        lockManager = new LockManager(dao, LockManagerSettings(UnlockMode.STRICT), lockableToken, underlyingToken);
+        dao.grant(address(lockManager), alice, lockManager.UPDATE_SETTINGS_PERMISSION_ID());
+        lockManager.setPluginAddress(plugin3);
     }
 
-    function test_WhenCallingGetSettings() external whenCallingUpdateSettings {
-        // It Should return the right value
-        vm.skip(true);
+    function test_WhenSetPluginAddressWithThePermission() external whenCallingSetPluginAddress {
+        // It should update the address
+
+        (, LockToVotePlugin plugin2,,,) = builder.build();
+        (, LockToVotePlugin plugin3,,,) = builder.build();
+
+        lockManager = new LockManager(dao, LockManagerSettings(UnlockMode.STRICT), lockableToken, underlyingToken);
+        dao.grant(address(lockManager), alice, lockManager.UPDATE_SETTINGS_PERMISSION_ID());
+        lockManager.setPluginAddress(plugin2);
+        assertEq(address(lockManager.plugin()), address(plugin2));
+
+        // OK 2
+
+        lockManager = new LockManager(dao, LockManagerSettings(UnlockMode.STRICT), lockableToken, underlyingToken);
+        dao.grant(address(lockManager), alice, lockManager.UPDATE_SETTINGS_PERMISSION_ID());
+        lockManager.setPluginAddress(plugin3);
+        assertEq(address(lockManager.plugin()), address(plugin3));
     }
 
     function test_WhenCallingSupportsInterface() external {
diff --git a/test/LockManager.t.yaml b/test/LockManager.t.yaml
index 0aaaea7..294b00b 100644
--- a/test/LockManager.t.yaml
+++ b/test/LockManager.t.yaml
@@ -8,19 +8,16 @@ LockManagerTest:
         then:
           - it: Registers the DAO address
           - it: Stores the given settings
-          - it: Stores the given plugin and token addresses
+          - it: Stores the given token addresses
 
-  - when: calling updateSettings
+  - when: calling setPluginAddress
     and:
-      - when: updateSettings without the permission
+      - when: setPluginAddress without the permission
         then:
           - it: should revert
-      - when: updateSettings with the permission
+      - when: setPluginAddress with the permission
         then:
-          - it: should update the mode
-      - when: Calling getSettings
-        then:
-          - it: Should return the right value
+          - it: should update the address
 
   - when: calling supportsInterface
     then:
diff --git a/test/util/DaoBuilder.sol b/test/util/DaoBuilder.sol
index 298a415..0c7c327 100644
--- a/test/util/DaoBuilder.sol
+++ b/test/util/DaoBuilder.sol
@@ -107,6 +107,10 @@ contract DaoBuilder is Test {
                     )
                 )
             );
+
+            dao.grant(address(helper), address(this), helper.UPDATE_SETTINGS_PERMISSION_ID());
+            helper.setPluginAddress(plugin);
+            dao.revoke(address(helper), address(this), helper.UPDATE_SETTINGS_PERMISSION_ID());
         }
 
         // The plugin can execute on the DAO