Forty years ago, the Kaiser Research group pioneered an approach t o interpersonal assessment based on a structural model of personality, the interpersonal circle. With renewed interest in circular models, issues about the measurement, analysis, and application of these kinds of individual data reemerge. This article is an introduction t o and revision of the b u i c principles of circular profile analysis. Using the recent circumplex of interpersonal problems, we define the model and its data, explain the structural summary, and discuss the descriptive and possible clinical significance of profile indices. Future researchers should seek t o expand understanding of how circular profile variables relate to clinical assessment and treatment, and also apply the analytic methods t o test key aspects of interpersonal theory.(2) The variables ofapersonality system should be designed to measure-on the same continuum-the normal or "adjustive" aspects ofbehavior as well as abnormal or pathological extremes. (3) Measurement of interpersonal behavior requires a broad collection of simple, specijc variables which are systematically related to each other and which are applicable to the study of adjustive or maladjustive responses. Correspondence regarding this article can be directed to either author: Michael B. G u m , Psychology Department, University ofWisconsin-Parkside, Kenosha. WI 53141; orJ. D. Balakrishnan, Department of Psychological Sciences, Purdue University, West Lafayette, IN 47907. Electronic mail may be sent via Internet to gurtman@uwp.edu.