diff --git a/lib/gitlab/user_team_manager.rb b/lib/gitlab/user_team_manager.rb
new file mode 100644
index 00000000000..d010c79223e
--- /dev/null
+++ b/lib/gitlab/user_team_manager.rb
@@ -0,0 +1,93 @@
+# UserTeamManager class
+#
+# Used for manage User teams with project repositories
+module Gitlab
+  class UserTeamManager
+    class << self
+      def assign(team, project, access)
+        project = Project.find(project) unless project.is_a? Project
+        searched_project = team.user_team_project_relationships.find_by_project_id(project.id)
+
+        unless searched_project.present?
+          team.user_team_project_relationships.create(project_id: project.id, greatest_access: access)
+          update_team_users_access_in_project(team, project)
+        end
+      end
+
+      def resign(team, project)
+        project = Project.find(project) unless project.is_a? Project
+
+        team.user_team_project_relationships.with_project(project).destroy_all
+
+        update_team_users_access_in_project(team, project)
+      end
+
+      def update_team_users_access_in_project(team, project)
+        members = team.members
+        members.each do |member|
+          update_team_user_access_in_project(team, member, project)
+        end
+      end
+
+      def update_team_user_access_in_project(team, user, project)
+        granted_access = max_teams_member_permission_in_project(user, project)
+
+        project_team_user = UsersProject.find_by_user_id_and_project_id(user.id, project.id)
+
+        if project_team_user.present?
+          project_team_user.destroy
+        end
+
+        if project_team_user.blank? && granted_access > 0
+          UsersProject.add_users_into_projects([project.id], [user.id], granted_access)
+        end
+      end
+
+      def max_teams_member_permission_in_project(user, project, teams = nil)
+        result_access = 0
+
+        user_teams = project.user_teams.with_member(user)
+
+        teams ||= user_teams
+
+        if teams.any?
+          teams.each do |team|
+            granted_access = max_team_member_permission_in_project(team, user, project)
+            result_access = [granted_access, result_access].max
+          end
+        end
+        result_access
+      end
+
+      def max_team_member_permission_in_project(team, user, project)
+        member_access = team.default_projects_access(user)
+        team_access = team.user_team_project_relationships.find_by_project_id(project.id).greatest_access
+
+        [team_access, member_access].min
+      end
+
+      def add_member_into_team(team, user, access, admin)
+        user = User.find(user) unless user.is_a? User
+
+        team.user_team_user_relationships.create(user_id: user.id, permission: access, group_admin: admin)
+        team.projects.each do |project|
+          update_team_user_access_in_project(team, user, project)
+        end
+      end
+
+      def remove_member_from_team(team, user)
+        user = User.find(user) unless user.is_a? User
+
+        team.user_team_user_relationships.with_user(user).destroy_all
+        other_teams = []
+        team.projects.each do |project|
+          other_teams << project.user_teams.with_member(user)
+        end
+        other_teams.uniq
+        unless other_teams.any?
+          UsersProject.in_projects(team.projects).with_user(user).destroy_all
+        end
+      end
+    end
+  end
+end