GUEST EDITORIAL: INTRODUCTION TO THE SPECIAL SECTION.

One of the main goals of software engineering is to provide methods to master complexity by practitioning large software systems into simpler components that can be addressed separately. A number of methods and techniques, distilled from experience and best practices, have been published in the literature to help software engineers in the application of the principle of divide and conquer to software systems development. A complex system can be characterized as a system whose properties cannot be studied by suitably decomposing it into components, but rather depend heavily on the interactions among such components. Some systems are inherently complex, that is, there is no way to identify components that simplify the analysis, in other cases, complexity may derive from the current lack of knowledge or experience, especially when new technologies are introduced and new application areas are discovered. The papers selected for this special section of the January/February issue of the journal IEEE Transactions on Software Engineering, are representative of the ideas presented at the IEEE International Conference on Engineering Complex Computer Systems, held in Como, Italy. This special section presents four papers selected from those presented at the conference.