Paul Clements is a Senior Member of the Technical Staff at the Carnegie Mellon Software Engineering Institute (SEI), where he has worked since 1994 leading or coleading projects in software product-line engineering and software architecture documentation and analysis. Besides this one, Clements is the coauthor of two other practitioner-oriented books about software architecture: Software Architecture in Practice (Addison-Wesley, 1998; Second Edition 2003) and Evaluating Software Architectures: Methods and Case Studies (Addison-Wesley, 2001). He also cowrote Software Product Lines: Practices and Patterns (Addison-Wesley, 2001) and was coauthor and editor of Constructing Superior Software (Sams, 1999). In addition, Clements has authored dozens of papers in software engineering, reflecting his longstanding interest in the design and specification of challenging software systems. In 2005 and 2006 he spent a year as a visiting faculty member at the Indian Institute of Technology in Mumbai. He received a Ph.D. in computer sciences from the University of Texas at Austin in 1994. He is a founding member of the IFIP Working Group on Software Architecture (WG2.10).