Have a look at Addressing Dis-integration for the most practical advice about what to do in the real life dilemmas that trying to work with different professionals and different agencies tends to throw up.
There are Interprofessional Boundaries that help to preserve effective postive relationships across professional groups and agencies.
You may wish to use How to speak to a... to help get the best out of conversations with other ProfessionalNetworkMembers (for instance, this includes material on How to speak to a SOCIAL WORKER, or a DOCTOR, etc...
See the Dis-integration grid for a way to assess potential breaks in the continuity of the care network that might need addressing. See aso Dis-integrative processes in a Multi-Agency context for discussion on how things can get into a muddle when trying to coordinate across such networks.