This book contains the final reports of 19 workshops held during the 20th European Conference on Object-Oriented Programming, ECOOP 2006, held in Nantes, France in July 2006. The 19 reports cover the entire range of object technology and related topics, presenting a coherent and highly representative snapshot of the major trends in the field.

This book constitutes the thoroughly refereed post-proceedings of the 5th International Workshop on Software Composition, SC 2006, a satellite event of the European Joint Conferences on Theory and Practice of Software, ETAPS 2006. The book presents 21 revised full papers reflecting current research in software composition to foster development of composition models and techniques by using aspect-oriented programming, specification of component contracts and protocols, and methods of correct components composition.

The LNCS Transactions on Modularity and Composition are devoted to all aspects of software modularity and composition methods, tools, and techniques, covering requirement analysis, design, implementation, maintenance, and evolution. The focus of the journal also includes modelling techniques, new paradigms and languages, development tools, measurement, novel verification and testing approaches, theoretical foundations, and understanding interactions between modularity and composition. This, the first issue of the Transactions on Modularity and Composition, consists of two sections. The first one, guest edited by Patrick Eugster, Mario Sudholt, and Lukasz Ziarek, is entitled "Aspects, Events, and Modularity" and includes papers focusing on context-oriented software development, specifications for even-based systems, and development of modular software. The second section, guest edited by Gary T. Leavens, contains journal versions of selected papers from Modularity 2015, which was held in March 2015, in Fort Collins, Colorado, USA. Topics covered by the papers in this section include software unbundling, layer activation in context-oriented programming, modular reasoning in event-based languages, and dynamic dispatch for method contracts using abstract predicates. The paper 'Dynamic Dispatch for Method Contracts Through Abstract Predicates' is published open access under a CC BY 4.0 license at link.springer.com.