Understanding evolution in systems of systems

Based on a literature analysis, this paper examines the nature of evolution in Systems of Systems (SoS) by attempting to answer why, where and how change occurs in this new kind of complex systems as well as what unprecedented underlying challenges makes it difficult to manage. This paper gives special focus on how state-of-the-art research efforts are attempting to solve those challenges and ultimately aims to provide research directions towards making evolution in systems of systems a disciplined activity.