Writing this book has been part of my life for about five years. It would have been impossible to ever get it finished without the collaboration, friendship, love and support of so many people. I would like to explicitly mention them here and acknowledge their importance for finally reaching the finish line. Collaboration with other researchers and students has always been a fascinating part of my life. It is stimulating to share ideas, to get comments and suggestions, and to jointly create solutions. During the five-year period, and in the context of this book, I was fortunate to work with many people across the world.

Research is the result of discussion and interactions. Des Greer (Queens University of Belfast) was the one with whom I started to look at the whole area of product release planning in 2002, when we developed the first ideas and a systematic solution method called EVOLVE. This collaboration is still ongoing, and has substantially contributed to this book. Both Dietmar Pfahl (University of Oslo) and Armin Eberlein (American University of Sharjah) have provided constructive comments and suggestions on earlier versions of the book. Their support was tremendously helpful to make the text more readable and easier to understand.

An Ngo-The (Pelsea, Calgary) has been a close collaborator of mine since 2003. His background and expertise were very valuable for developing some of the methods and techniques presented in this book. Among the many others, I want to explicitly mention Joerg Denzinger, Michael M. Richter, Jonathan Silito from University of Calgary and Luigi Troiano (University of Sannio) and Tom Zimmerman (Microsoft Research). The ATMAN collaboration project with the Helsinki University of Technology gave me the opportunity to collaborate with a number of colleagues, especially with Ville Heikkilae, Kristian Rautiainen and Jarno Vahaniitty.

Research is the result of discussion and interactions. Working with students is one of the most fascinating things in my professional career. My former and existing students Jingzhou Li, Gengshen Du, Omolade Saliu and Ahmed Al-Emran deserve special acknowledgement for their contribution to Sections 9.2, 9.3, 9.4 respectively 9.5 of the book. The work of Anas Jadallah and Emad Livani has been of great help to perform the case studies of Chapters 7, 12, and 13. Comments and feedback to earlier versions of chapters of the book were provided by Sebastian Maurice, Jim McElroy, Elham Paikari, Mainur M. Rahman, Christoph Streb and Irfan Ullah.

The decision support tools presented in this book have been implemented over a period of six years. A number of students and professionals have contributed to that. Special thanks for their work are due to Amandeep Azad, Eric Bauld, Pankaj Bhawnani, Stephen Bosch, Brad Cossette, Devlin Dunsmore, Martin Echtner, Johannes Fischer, David Goodladd, Julian Gamble, Mark Przepiora, Greg Spiers and Kenny Tsang. The tools have matured over time as a result of a large number of trial users and a substantial number of graduate and undergraduate student projects conducted at the University of Calgary’s departments of Computer Science as well as Electrical and Computer Engineering.

I cannot stress enough the importance of the interaction with industry from the very beginning. Their immediate response and ongoing request to address new questions have been a stimulating factor: Ville Hamalainen (Stonesoft), Janne Jarvinen, (F-Secure), Eduard Kaiser and Andreas Reh (Siemens Audiology), Puneet Kapur (Chartwell Technology), Franz Kudorfer (Siemens Corporate Technology), Mike McAllister (SAP Canada), Peter McCurdy (Nortel Networks), Ludger Meyer (Siemens Corporate Technology), Joseph Momoh (Trema Laboratories), the late Andrew Smith (Chartwell Technology), Hamid Sarreshtehdari (National Research Council) and Mark Stanford (iGrafx).

Parts of the research have been supported by various funding agencies. The financial support of the Alberta Informatics Circle of Research Excellence (iCORE), the Natural Sciences and Engineering Research Council of Canada NSERC, the National Research Council of Canada NRC, and the Alberta Ingenuity Fund AIF is highly appreciated.

Many thanks are also due to the publishers from CRC Press. Special thanks to John Wyzalek for his never-ending patience and support.

Friends and family always provided the essential emotional support to keep the fire burning. In particular, it was and is Kornelia Streb who has done even more than that. Her technical excellence has helped to visualize things I could not express myself. She has devoted endless patience and energy to design figures, prepare tables, screen-shots and finally putting the whole text together.