MOST BEHAVIORAL THERAPY EFFORTS AT THE TIME OF THE STUDY INCLUDED THE ENTIRE FAMILY OF THE DELINQUENT IN CONTINUING TREATMENT: THE RATIONALE BEHIND THE FAMILY FOCUS RESTS ON THEORY AND RESEARCH ESPOUSING A SYSTEMS VIEW OF MALADAPTIVE BEHAVIOR. WITHIN THIS FRAMEWORK, 'SYMPTOMS' OF THE INDIVIDUAL ARE SEEN AS HAVING A FUNCTIONAL SIGNIFICANCE WHICH CAN BE UNDERSTOOD WITHIN THE CONTEXT OF THAT PERSON'S SOCIAL OR INTERPERSONAL MATRIX. BY EXTENSION, CHANGE IN THE INDIVIDUAL (I.E., THE DELINQUENT) CAN BE ACHIEVED THROUGH A RESTRUCTURING OF THE INTERACTION AT THE LEVEL OF THE LARGER SOCIAL UNIT (I.E., THE FAMILY). THE STUDY WAS DEVISED TO DETERMINE EMPIRICALLY WHICH INTERVENTION, INDIVIDUALORIENTED BEHAVIOR THERAPY (IOBT), OR FAMILY-ORIENTED BEHAVIOR THERAPY (FOBT), IS MORE EFFECTIVE IN THE TREATMENT OF DELINQUENCY. IT WAS EXPECTED THAT THE FAMILY FOCUS WOULD PROVIDE FOR GREATER IMPROVEMENT ON PROCESS MEASURES AND FEWER CASES OF RECIDIVISM THAN THE INDIVIDUAL FOCUS. EXPERIMENTAL SUBJECTS AND CONTROLS WERE STATUS OFFENDER YOUTHS AND THEIR FAMILIES REFERRED TO THE UNIVERSITY OF VIRGINIA'S DEPARTMENT OF PSYCHOLOGY BY THE JUVENILE COURT AND OTHER SOCIAL SERVICE AGENCIES IN CHARLOTTESVILLE, VIRGINIA. THE NAMES, COURT RECORDS, AND DEMOGRAPHIC CHARACTERISTICS OF EACH FAMILY WERE SECURED FROM A COURT-APPOINTED PROBATION OFFICER. THE 24 ADOLESCENT STATUS OFFENDERS AND THEIR FAMILIES WERE RANDOMLY ASSIGNED TO 1 OF 3 EXPERIMENTAL CONDITIONS: FOBT; IOBT; OR A WAITING LIST CONTROL CONDITION, IN WHICH TREATMENT WAS DEFERRED PENDING COMPLETION OF THE STUDY. FOLLOWING A SERIES OF 8 1-HOUR TREATMENT SESSIONS, CLEAR BEHAVIORAL OUTCOME DIFFERENCES WERE FOUND BETWEEN GROUPS, WITH FOBT RESULTING IN SIGNIFICANTLY FEWER CASES OF COURT REFERRAL THAN IOBT OR CONTROLS. CONSISTENT, ALTHOUGH LESS CONCISE, EVIDENCE IN BEHALF OF THE GREATER EFFECTIVENESS OF FOBT WAS FOUND ALONG THERAPEUTIC PROCESS DIMENSIONS. NO IMPROVEMENTS WERE FOUND FOR IOBT AS COMPARED WITH NONTREATED CONTROLS. THE DIFFERENTIAL RESULTS FOR THESE TWO TREATMENTS ARE DISCUSSED FROM A SYSTEMS PERSPECTIVE. BACKGROUND INFORMATION, RESEARCH METHODOLOGY, AND RESULTS ARE DESCRIBED IN DEPTH. TABULAR DATA ARE INCLUDED THROUGHOUT, AND SUPPORTING DOCUMENTS ARE APPENDED. REFERENCES ARE PROVIDED. (AUTHOR ABSTRACT MODIFIED)