This volume gives a coherent presentation of the outcome of the project PROSPECTRA (PROgram development by SPECification and TRAnsformation) that aims to provide a rigorous methodology for developing correct software and a comprehensive support system. The results are substantial: a theoretically well-founded methodology covering the whole development cycle, a very high-level specification and transformation language family allowing meta-program development and formalization of the development process itself, and a prototype development system supporting structure editing, incremental static-semantic checking, interactive context-sensitive transformation and verification, development of transformation (meta-) programs, version management, and so on, with an initial library of specifications and a sizeable collection of implemented transformations. The intended audience for this documentation is the academic community working in this and related areas and those members of the industrial community interested in the use of formal methods.