PMS/PyPubSub (short for Python Message Service / Python based Publish Subscribe) is a framework for implementing a publish subscribe mechanism into a Python application. A python process somewhere in the network publishes one or more topics which consist of Python objects. Multiple processes in the network can subscribe to fresh updates of the published topics. A publisher and its subsribers are fully decoupled. The datatype of a topic can be freely defined and changed at runtime. New publishers and subscribers can easily be added at runtime.