As reflected in the 12 chapters of this book, the achievements of psychoanalysis during its first hundred years have been extraordinary. Each chapter is written by psychoanalysts strongly committed to a particular version of psychoanalytic theory and practice. The most notable shift in psychoanalysis has been from the one-person or intrapsychic model of psychoanalysis to the interaction or interpersonal, two-person version. It is the two-person model that characterizes every chapter in this book. All of the contributors to this book are committed to efforts to revise the basic propositions of psychoanalysis and to extend the effectiveness of its clinical applications and techniques.