This book constitutes the thoroughly refereed proceedings of the 46th International Conference on Objects, Components, Models and Patterns, TOOLS EUROPE 2008, held in Zurich, Switzerland, in June/July 2008. The 21 papers presented in this book were carefully reviewed and selected from 58 submissions. TOOLS played a major role in the spread of object-oriented and component technologies. It has now broadened its scope beyond the original topics of object technology and component-based development to encompass all modern, practical approaches to software development. At the same time, TOOLS kept its traditional spirit of technical excellence, its acclaimed focus on practicality, its well-proven combination of theory and applications, and its reliance on the best experts from academia and industry.