Personality pathology is rooted in early development and affects a wide range of affects, behaviours and cognitive processes. Every year thousands of articles about the etiology pf personality pathology are published in various professional or scientific reviews. There is a growing distance between the generalist’s practice and our increasingly precise scientific knowledge. However, no one can read everything and therefore, it behoves us to ask ourselves the following questions: is the most recent better than what came before? Is the measurable and demonstrable necessarily clinically interesting? Must what interests the clinician be measured and proved? Whilst theory and clinical research are becoming increasingly precise, innumerable socio-economic forces are pressing for a simplification in clinical practice. “Shrinks” are fashionable! They are everywhere: in the workplace, on television, on the radio. Their services are paid for by private or company insurance, provided that it is a “quick fix”, not too expensive, and that we do not indulge in vague meanderings round “mal de vivre”! Dissatisfaction with life! In short, the generalist today finds himself torn between two opposing forces. He seeks to practise from a secure base and to keep his knowledge up to date, while being aware that this in turn will give rise to an increasingly varied clinical practice, in which he deals with serious pathologies as well as working with patients requesting help in more ordinary situations. Whatever the profile of his practice the generalist has to be able to work with personality disorders and understand how they arise. This essential competence enables him to make informed clinical decisions. So, the modest aim of this book is to be of use to the generalist in his daily practice. Of course it does not exempt anyone from thinking and doing his own reading according to his interests and particular queries. The integrative structure which is the basis of this work is known both as Relational Psychotherapy and as Object Relational Gestalt-therapy. It is written for all psychotherapists interested in finding out about developmental issues. The reader who is not familiar with the clinical theory of relational psychotherapy will find in the first chapters, a synthesis of its main features. This should allow him to read and make wise clinical use of the chapters on the main developmental issues.