Parties providing health services must have access to relevant patient data. Data sharing is common, as healthcare environments involve the collaboration of care providers, often across organisational structures. Whilst data availability is crucial to the care process, the confidential nature of medical information means that data must also be protected. To assist in the new data management concerns of distributed health systems, this paper introduces a model, built upon publish-subscribe mechanisms, for controlling the flow of data in a multi-domain homecare environment.