This book has received a good deal of help. My largest debt is to my colleague and codirector Renate Mayntz, who not only shares the credit for formulating the framework of "actor-centered institutionalism" ( Mayntz/ Scharpf 1995a) but who also, more than anybody else, has influenced my way of thinking about and of doing social science research. I have profited so much from our collaboration and discussion over more than a quarter of a century precisely because we have continued to see the world through sufficiently distinct lenses to make agreement something that was to be striven for rather than to be taken for granted. In the same spirit, I cannot claim, except where otherwise noted, that Renate would approve of all that is in this book, even though she has read an of it and given me the benefit of her comments.
My second debt is to the students at the University of Konstanz who responded to the ideas presented here in two seminar courses, one before the serious writing began, the other after a first draft was completed. At that stage I also received valuable comments from Kjell Hausken at our institute. The next push came then from Margaret Levi at the University of Washington, Seattle, and Adrienne Héritier at the European University Institute, Florence, both of whom agreed to review the second draft from the critical but on the whole sympathetic perspective of colleagues dealing with similar challenges in their own work. Their comments encouraged me to insist more boldly that theoretically disciplined explanations can be achieved even when we study potentially unique policy interactions and that a framework for policy research must reflect the normative as well as the positive dimensions of its subject. Around the same time, Marlene Brockmann did me the favor of going over the whole text with the red pencil of the professional writer and editor. If the result is at all readable, the credit must go to her.
The greatest influence on the substance and style of the book came from Paul Sabatier, the editor of the "Theoretical Lenses" series. He suggested the present format at a time when my plans were still malleable, and he also did me the favor of going through the manuscript, practically sentence by sentence, with editorial suggestions on every chapter and again on later versions of chapters that he had disliked initially or where I had initially disliked his comments. Given his superb editorial skills and his ever tactful insistence, I usually ended up liking what he did. I can only hope that he will also like the final version.