The many faces of complexity in software design

‘Complexity’ and ‘crisis’ have become synonyms in the (brief) history of Software Engineering. The terms ‘component’, ‘decomposition’, ‘structure’ and ‘architecture’ have been associated with methods and techniques proposed over the years to defeat the crisis, from structured programming to object/component based programming and, more recently, service-oriented architectures. This chapter discusses the nature of complexity as it arises in software design, assesses the progress that we have achieved in tackling it, and discusses some of the challenges that still remain.