ABSTRACT A theory of personality should lead to both accurate prediction and interpretive understanding. Aside from its empirical uses, a personality theory should provide a grammar that allows personality psychologists to infer meaning from overt behavior with more sophistication than a layperson, and the best laboratory for testing the interpretive utility of a personality theory remains the clinic. With respect to the appropriate data for constructing and evaluating theories of personality, an overreliance on questionnaire data is problematic for several reasons: It assumes that understanding people requires no training, it mistakes research on the conscious self-concept for research on personality, it conflates implicit and explicit knowledge, it fails to address defensive biases, and it lacks interrater reliability. Consideration of both empirical and clinical data points to three questions that define the elements of personality necessary for a comprehensive assessment of an individual: (a) What psychological resources–cognitive, affective, and behavioral dispositions–does the individual have at his or her disposal? (b) What does the person wish for, fear, and value, and how do these motives combine and conflict? (c) How does the person experience the self and others, and to what extent can the individual enter into intimate relationships?