A software distribution system comprises building blocks including a preparation and test site, comprising a software package editor, software package transformation tools and an AutoPack module for preparing and testing software packages to be distributed to endpoints. A software package comprises a file including a complete definition of the actions involved in a software distribution and, once distributed, when a software package is available to a target endpoint, an engine resident on the target can be instructed via the management agent to decode the software package from the file into memory and then to perform various software distribution operations including installing, removing and modifying the software and configuration of the endpoint.