Our interest is in formal models of the specification process. In recent years, there have been a number of small-scale studies investigating the feasibility of automating some or all of the specification process. Unfortunately, because the field is quite young, each project team has been forced to invent their own vocabulary to describe their results. This makes it difficult to compare two projects and identify their similarities and differences.

In this paper we propose a single model of specification, the composition model. We claim that three recent projects exploring automated specification are all based on the same model. The three projects are the Requirements Apprentice [Reubenstein 91], the IDeA / ROSE project [Lubars 89], and the ASAP/ OPIE project [Anderson and Fickas 89]. We first describe the general model, then discuss the individual differ­ences between the three projects.