As collaboration activities usually involve several people with different group tasks and needs, they are rarely supported by a single CSCW technology. Then different types of collaborative applications are usually applied in order to support group work. But in spite of being used to accomplish a common collaboration task, these applications are executed independently without getting any advantage of each other. The integration of such applications would allow them to dynamically interoperate, combining their different functionalities in a controlled way. In order to achieve integration, we propose LEICA, a loosely-coupled integration environment which allows collaborative applications to interact without loosing their autonomy. LEICA relies on Web services technology, event notification system, and collaboration policies for controlling the interactions between integrated applications.