diff --git a/src/endpoints/collections.ts b/src/endpoints/collections.ts
index 12c5bf5..75a2eed 100644
--- a/src/endpoints/collections.ts
+++ b/src/endpoints/collections.ts
@@ -1,8 +1,12 @@
 import { orm } from '../orm/orm';
 import { UnwrappedRequest } from '../utilities/guard';
 import { CreatedResponse, ErrorResponse, OkResponse } from '../utilities/responseHelper';
-import { CreateCollectionRequest, UpdateCollectionRequest } from '../utilities/requestModels';
-import { CollectionId } from '../utilities/secureIds';
+import {
+    GameToCollectionRequest,
+    CreateCollectionRequest,
+    UpdateCollectionRequest,
+} from '../utilities/requestModels';
+import { CollectionId, GameId } from '../utilities/secureIds';
 
 async function create(request: UnwrappedRequest<CreateCollectionRequest>): Promise<Response> {
     try {
@@ -47,10 +51,40 @@ async function drop(request: UnwrappedRequest): Promise<Response> {
     }
 }
 
+async function addGame(request: UnwrappedRequest<GameToCollectionRequest>): Promise<Response> {
+    try {
+        return new OkResponse(
+            await orm.collections.addGame(
+                CollectionId.fromHash(request.params.id),
+                GameId.fromHash(request.body.gameId),
+                request.claims,
+            ),
+        );
+    } catch (error: any) {
+        return new ErrorResponse(error as Error);
+    }
+}
+
+async function removeGame(request: UnwrappedRequest<GameToCollectionRequest>): Promise<Response> {
+    try {
+        return new OkResponse(
+            await orm.collections.removeGame(
+                CollectionId.fromHash(request.params.id),
+                GameId.fromHash(request.body.gameId),
+                request.claims,
+            ),
+        );
+    } catch (error: any) {
+        return new ErrorResponse(error as Error);
+    }
+}
+
 export default {
     create,
     get,
     list,
     update,
     drop,
+    addGame,
+    removeGame,
 };
diff --git a/src/orm/collections.ts b/src/orm/collections.ts
index 0863c77..9bbc7e9 100644
--- a/src/orm/collections.ts
+++ b/src/orm/collections.ts
@@ -127,4 +127,41 @@ export class CollectionsOrm {
 
         return;
     }
+
+    async addGame(id: CollectionId, gameId: GameId, claims: Claims): Promise<void> {
+        const collection = await this.get(id);
+        if (!(Claims.test(Claims.ADMIN, claims) || Claims.test(Claims.COLLECTIONS.UNOWNED.GAME.ADD, claims))) {
+            throw new UnauthorizedError();
+        } else if (
+            Claims.test(Claims.COLLECTIONS.OWNED.GAME.ADD, claims) &&
+            claims?.userId &&
+            collection.id !== claims.userId
+        ) {
+            throw new UnauthorizedError();
+        }
+
+        await sql`INSERT INTO collection_games (collection_id, game_id)
+                  VALUES (${id.raw}, ${gameId.raw})`;
+
+        return;
+    }
+    async removeGame(id: CollectionId, gameId: GameId, claims: Claims): Promise<void> {
+        const collection = await this.get(id);
+        if (!(Claims.test(Claims.ADMIN, claims) || Claims.test(Claims.COLLECTIONS.UNOWNED.GAME.REMOVE, claims))) {
+            throw new UnauthorizedError();
+        } else if (
+            Claims.test(Claims.COLLECTIONS.OWNED.GAME.REMOVE, claims) &&
+            claims?.userId &&
+            collection.id !== claims.userId
+        ) {
+            throw new UnauthorizedError();
+        }
+
+        await sql`DELETE
+                  FROM collection_games
+                  WHERE collection_id = ${id.raw}
+                    AND game_id = ${gameId.raw}`;
+
+        return;
+    }
 }
diff --git a/src/routes/collections.ts b/src/routes/collections.ts
index 67c03ff..191e8fb 100644
--- a/src/routes/collections.ts
+++ b/src/routes/collections.ts
@@ -11,6 +11,20 @@ export default {
         // PATCH: guard(collections.update, [Claims.ADMIN, Claims.PLAYERS.OTHER.UPDATE, Claims.PLAYERS.SELF.UPDATE]),
         // DELETE: guard(collections.drop, [Claims.ADMIN, Claims.PLAYERS.OTHER.DELETE, Claims.PLAYERS.SELF.DELETE]),
     },
+    '/api/collection/:id/add': {
+        POST: guard(collections.addGame, [
+            Claims.ADMIN,
+            Claims.COLLECTIONS.UNOWNED.GAME.ADD,
+            Claims.COLLECTIONS.OWNED.GAME.ADD,
+        ]),
+    },
+    '/api/collection/:id/remove': {
+        POST: guard(collections.removeGame, [
+            Claims.ADMIN,
+            Claims.COLLECTIONS.UNOWNED.GAME.REMOVE,
+            Claims.COLLECTIONS.OWNED.GAME.REMOVE,
+        ]),
+    },
     '/api/collection/list': {
         GET: guard(collections.list, [Claims.ADMIN, Claims.COLLECTIONS.OWNED.LIST]),
     },
diff --git a/src/utilities/claimDefinitions.ts b/src/utilities/claimDefinitions.ts
index c78b56f..1f0ce0f 100644
--- a/src/utilities/claimDefinitions.ts
+++ b/src/utilities/claimDefinitions.ts
@@ -108,6 +108,10 @@ export class ClaimDefinition {
             UPDATE: 'COLLECTIONS_OWNED_UPDATE',
             DELETE: 'COLLECTIONS_OWNED_DELETE',
             LIST: 'COLLECTIONS_OWNED_LIST',
+            GAME: {
+                ADD: 'COLLECTIONS_OWNED_GAME_ADD',
+                REMOVE: 'COLLECTIONS_OWNED_GAME_REMOVE',
+            },
             COMMENTS: {
                 DELETE: 'COLLECTIONS_OWNED_COMMENTS_DELETE',
             },
@@ -116,6 +120,10 @@ export class ClaimDefinition {
             READ: 'COLLECTIONS_UNOWNED_READ',
             UPDATE: 'COLLECTIONS_UNOWNED_UPDATE',
             DELETE: 'COLLECTIONS_UNOWNED_DELETE',
+            GAME: {
+                ADD: 'COLLECTIONS_UNOWNED_GAME_ADD',
+                REMOVE: 'COLLECTIONS_UNOWNED_GAME_REMOVE',
+            },
         },
     };
     public static readonly COMMENTS = {
diff --git a/src/utilities/requestModels.ts b/src/utilities/requestModels.ts
index 324b600..330e64c 100644
--- a/src/utilities/requestModels.ts
+++ b/src/utilities/requestModels.ts
@@ -47,3 +47,6 @@ export interface CreateCollectionRequest {
 export interface UpdateCollectionRequest {
     name?: string;
 }
+export interface GameToCollectionRequest {
+    gameId: string;
+}
\ No newline at end of file