The types of awareness relevant to collaborative software engineering are identified and an additional type, "historical awareness" is proposed. This new type of awareness is the knowledge of how software artefacts resulting from collaboration have evolved in the course of their development. The types of awareness that different software engineering environment architectures can support are discussed. A way to add awareness support to our existing OSCAR system, a component of the GENESIS software engineering platform, is proposed. Finally ways of instrumenting and evaluating the awareness support offered by the modified system are outlined.