This tutorial book presents an augmented selection of material presented at the International Summer School on Generative and Transformational Techniques in Software Engineering, GTTSE 2005. The book comprises 7 tutorial lectures presented together with 8 technology presentations and 6 contributions to the participants workshop. The tutorials combine foundations, methods, examples, and tool support. Subjects covered include feature-oriented programming and the AHEAD tool suite; program transformation with reflection and aspect-oriented programming, and more.