In our current professional climate, with calls for 'evidenced-based treatment', and in light of the prestige accorded to this emblem, we can ask: for what purpose do we seek evidence? For our students? For the public at large? For an inner sense of feeling supported by science? Most disciplines are concerned with cumulative knowledge, aimed toward self-affirmation and self-definition, that is, establishing a sense of legitimacy. The three parts of this volume are directed toward the goal of affirming a public and private sense of the legitimacy of psychoanalysis, thereby shaping professional identity. In each contribution we adhere to the precepts of 'scientific inquiry', with a commitment to affirming or disconfirming clinical propositions, utilizing consensually agreed upon methods of observation, and arriving at inferences that are persuasive and have the potential to move the field forward. Beyond this, each part of this book describes distinct methodologies that generate evidence pertaining to public health policy, the persuasiveness and integrity of our psychoanalytic concepts, and phenomena encountered in daily clinical practice.