Integrated project support environments (IPSEs) are intended to provide a cohesive and integrated set of tools to support the process of design and development in software engineering projects. Much current research is concentrated on maximising the degree to which these tools can be integrated. This paper briefly describes the architecture of a prototype IPSE which attempts to achieve a high degree of integration using techniques drawn from the disciplines of intelligent knowledge-based systems, office automation and object-oriented programming. The remainder of the paper deals with the design of a user interface to the IPSE based on direct manipulation. It argues that this provides a consistent and integrated method with which users can interact with the objects in the IPSE's object store.