The clinical interview is a collaborative process between a client and clinician. It establishes the assessment context and defines the presenting problem from a biopsychosocial framework by evaluating relevant factors, including the history and functional effects of the presenting problem, social history, coping style, and personal strengths and weaknesses. During the clinical interview, clinicians develop diagnostic hypotheses to be examined during the assessment process and determine the most effective methods to test these hypotheses. The clinical interview provides information for later use in case conceptualization, treatment recommendations, goal setting, and treatment planning. This chapter contains background information about the primary components of the clinical interview with sample questions provided throughout.