As software systems become ubiquitous, the issues of dependability become more and more crucial. Given that solutions to these issues must be considered from the very beginning of the design process, it is reasonable that dependability is addressed at the architectural level. This book was born of an effort to bring together the research communities of software architectures and dependability. This state-of-the-art survey contains 18 expanded and peer-reviewed papers based on the carefully selected contributions to the Workshop on Architecting Dependable Systems (WADS 2006), organized at the 2006 International Conference on Dependable Systems and Networks (DSN 2006), held in Philadelphia, PA, USA, in June 2006. It also contains a number of invited papers written by recognized experts in the area. The papers are organized in topical sections on architectural description languages, architectural components and patterns, architecting distributed systems, and architectural assurances for dependability.