The article presents an overview of the chronic depression construct in the Diagnostic and Statistical Manual of Mental Disorders (DSMs) since 1980, including developmental etiology and psychopathological patterns of the chronically depressed adult. Then the Cognitive Behavioral Analysis System of Psychotherapy (CBASP), an empirically supported psychotherapy and the only therapy developed specifically to treat chronic depression, is described. CBASP addresses the idiosyncratic problems of the chronically depressed adult using Situational Analysis, the Interpersonal Discrimination Exercise, and Behavioral Skill Training/Rehearsal techniques. The first two techniques are illustrated using a verbatim case example. (C) 2003 Wiley Periodicals, Inc.