This study was designed to investigate the effect of congruity of counselor and client diagnoses upon client-perceived success in counseling. The Missouri Diagnostic Classification Plan (MDCP) was used as the basic diagnostic method. Agreement in the 15 categories was related to client-perceived success of counseling. Sublects, all clients at the Oreon State University Counseling Center, were each diagndsed as his case was closed. Responfies to follow-up questionnaires, designed for this purpose, were tabulated with demographic information. The strength of the relationship between counselor-client diagnoses and perceived outcomes is demonstrated in both multiple counselor-client agreements and in counselor-client argument-disagreement. The results support the growing evidence that interperional sensitivity and openness of communication are vital characteristics of successful counselors. (KP) U.S. DEPARTMENT OF HEALTH, EDUCATION & WELFARE