Reoservice: coordination modeling tool. Coordination in SOA addresses dynamic topologies of interactions among services. Most efforts up to now have been focused on statically defined composition of services, e.g., using BPEL. To the best of our knowledge, there are no serious means to address the issues of dynamic coordination to accommodate continuously changing requirements. While BPEL is a powerful standard for service composition, it lacks support for typical coordination constraints, like synchronisation, mutual exclusion, and context-dependency.