diff --git a/src/controller/group.ts b/src/controller/group.ts
index 769d06f..f523536 100644
--- a/src/controller/group.ts
+++ b/src/controller/group.ts
@@ -1,8 +1,13 @@
 import { checkProjectAccess } from "@controller/projects";
 import { encryptClearField } from "@utils/decryption";
 import { IKeyRole } from "@models/AccessKey";
-import { Group } from "@models/Group";
+import { Group, IGroup } from "@models/Group";
 import { planLimits } from "../limits/plans";
+import { Permission } from "@models/Permission";
+import { convertIdsToPermissions } from "@controller/permission";
+
+export const mapGroup = async (projectId: string, group: IGroup) => (
+    { name: group.name, description: group.description, permissions: await convertIdsToPermissions(projectId, group.permissions) });
 
 export const listGroups = async (userId: string, projectId: string) => {
     const access = await checkProjectAccess(IKeyRole.VIEW)(userId, projectId);
@@ -10,8 +15,7 @@ export const listGroups = async (userId: string, projectId: string) => {
 
     const groups = await Group.find({ projectId: encryptClearField(String(access._id)) });
 
-    return groups.map(group => ({name: group.name, description: group.description,
-        permissions: group.permissions}));
+    return Promise.all(groups.map(group => mapGroup(projectId, group)));
 };
 
 export const getGroup = async (userId: string, projectId: string, groupName: string) => {
@@ -21,10 +25,10 @@ export const getGroup = async (userId: string, projectId: string, groupName: str
     const group = await Group.findOne({ projectId: encryptClearField(String(project._id)), name: encryptClearField(groupName) });
     if (group === null) return { code: 4009, message: "The provided group does not exist" };
 
-    return { name: group.name, description: group.description, permissions: group.permissions };
+    return mapGroup(projectId, group);
 }
 
-export const createGroup = async (userId: string, projectId: string, configuration: { name: string, description: string, permissions?: string[] }) => {
+export const createGroup = async (userId: string, projectId: string, configuration: IGroup) => {
     const access = await checkProjectAccess(IKeyRole.MANAGE)(userId, projectId);
     if ("code" in access) return access;
 
@@ -34,7 +38,11 @@ export const createGroup = async (userId: string, projectId: string, configurati
     const group = await Group.findOne({ projectId: encryptClearField(String(access._id)), name: encryptClearField(configuration.name) });
     if (group !== null) return { code: 4008, message: "The provided group name is already in use" };
 
-    // TODO: Check if permissions exist
+    if (configuration.permissions) {
+        let permissionsEncrypted = (configuration.permissions || []).map(permission => encryptClearField(permission));
+        configuration.permissions = (await Permission.find({ projectId: encryptClearField(String(access._id)),
+            permission: { $in: permissionsEncrypted } })).map(permission => permission.id);
+    }
 
     await Group.create({ ...configuration, projectId });
 
@@ -51,7 +59,7 @@ export const deleteGroup = async (userId: string, projectId: string, groupName:
     await group.deleteOne();
 }
 
-export const updateGroup = async (userId: string, projectId: string, groupName: string, config: { name?: string, description?: string, permissions?: string[] }) => {
+export const updateGroup = async (userId: string, projectId: string, groupName: string, config: IGroup) => {
     const access = await checkProjectAccess(IKeyRole.MANAGE)(userId, projectId);
     if ("code" in access) return access;
 
@@ -63,7 +71,11 @@ export const updateGroup = async (userId: string, projectId: string, groupName:
         if (newGroup !== null) return { code: 4008, message: "The provided group name is already in use" };
     }
 
-    // TODO: Check if permissions exist
+    if (config.permissions) {
+        let permissionsEncrypted = (config.permissions || []).map(permission => encryptClearField(permission));
+        config.permissions = (await Permission.find({ projectId: encryptClearField(String(access._id)),
+            permission: { $in: permissionsEncrypted } })).map(permission => permission.id);
+    }
 
     await group.updateOne(config);