Modeling of Systems and their context is done to support communciation
with stakeholders, to facilitate reasoning about system requirements and
design, to support decision making, and in general to create and
maintain understanding, insight, and overview. The challenge in modeling
is to find an appropriate abstraction level, and to make sufficient
progress.

In this paper we discuss how time-boxing and iteration over
multiple views and models helps to address both challenges. Time-boxing
and iteration fit in a broader modeling method that w e will discuss
briefly to provide background.
