This paper evaluates current object-oriented analysis methods and proposes some possible improvements. We start by describing software requirements definition activities and reviewing the concepts of data modeling and object-orientation. We then identify key principles of object-oriented analysis and judge a selection of emerging methods against these principles. Finally, a proposal is presented which attempts to avoid some of the identified shortcomings. The proposal provides a nested object-relationship-operation framework which is based on a consistent use of the object model, a strong notion of encapsulation and a clear distinction between the essential and the contingent properties of the modelled entities.