The term software engineering arose in the 1960s to emphasize that the production of software should not be an art, as it was then (and sometimes still is today), but an engineering discipline with a defined production process. As a consequence, approach models for the production of software were created, most noticeable the classic software life-cycle model (SLC), which decomposes the software production process into distinct steps that are intended to make stepwise planning, decision and implementation possible. However, the classic SLC, although theoretically appealing, has some disadvantages, most of all that it cannot be used as is in practice. This led to several extensions and modifications of the model, whereas a very promising one is the use of prototyping, which leads to a prototyping-oriented SLC. This paper first describes the problems with the classic approach model and how some of these problems can be solved by using a prototyping SLC. Then we describe TOPOS, a TOolset for Prototyping-Oriented Software development. Finally, we investigate how object-oriented programming, especially application frameworks, support a prototyping-oriented approach.