Eclipse is an integrated project support environment (IPSE) whose purpose is to support the development of software systems from the specification stage through to their operation and maintenance. It is being developed by a consortium of universities and companies with funding from the UK Science and Engineering Research Council and the national Alvey programme. Eclipse is a distributed IPSE using high-powered workstations and both local and wide area networks. This paper presents an overview of the Eclipse project and a more detailed description of Eclipse's distributed architecture.