The aim of this chapter is to introduce basic notions of software engineering, to stress the importance of software engineering in general and of software development environments in particular, to introduce the problem areas a developer is facing when trying to build a new software development environment, to give an overview of the IPSEN project, to discuss the highlights of the project, to relate IPSEN to other software development environment projects, and to introduce the structure of this book. The generalpart of this chapter consists of the introduction of basic notions, the discussion of the importance and important topics of software engineering or software development environments (abbr. SDEs in the following) in section 1.1 or 1.2. Furthermore, an introduction to problem areas in software development environments research and realization is given in section 1.3 and a classification of SDEs in section 1.2 but especially in section 1.7. All these topics are IPSEN independent and, therefore, a discussion about software engineering and software development environments in general. However, as there is no common terminology available in software engineering, some of the notions (working area, extended technical configuration, administration configuration, and overall configuration model) have been developed in the context of the IPSEN project. Therefore, these notions express a very personal view on software engineering. The IPSEN overview and highlighting is done by different sections: In 1.4 we sketch that the integration problem is a key problem of software development environments which remains unsolved today. Therefore, environments nowadays lack user acceptance. One of the main motivations of the IPSEN research project is to give solutions to this problem. Section 1.5 gives a sketch of the uniform approach we have taken in IPSEN, called graph technology: Modelling documents as graphs, tools as graph processors, and giving a formal specification for both. The software engineering results of the IPSEN SDE are described in terms of a framework architecture containing standard components and derived specific components. Furthermore, a generator tool machinery in section 1.6. So, the highlights of IPSEN are results due to integration, graph technology, and architecture investigations of SDEs. The third part of this chapter consists of statements positioning IPSENin the SDE world and relating it to other SDE approaches. This is done by describing the variety of SDEs in section 1.2, by explaining the results of IPSEN due to the SDE problem area grouping of section 1.3, by classifying IPSEN according to a scheme for arbitrary SDEs in section 1.7, and by sketching the history, the current state, and the future work in section 1.8. At the end of the chapter we summarize and give an overview of the chapter and the structure of this book. For the latter, we describe the structure of the main chapters and their relationships by a structure and dependency graph.