THE PRINCIPAL COMPLETED PROJECTS IN THE RAND CORPORATION'S CRIMINAL CAREER RESEARCH PROGRAM INCLUDE (1) A STUDY OF CRIMINAL CAREERS INVOLVING INTERVIEWS WITH 49 PRISON INMATES, WHO HAD EACH SERVED AT LEAST ONE TERM PRIOR TO THEIR CURRENT CONVICTION AND WHO WERE CURRENTLY SERVING SENTENCES FOR ROBBERY; (2) A SURVEY OF 624 CALIFORNIA PRISON INMATES CONCERNING THEIR CURRENT CONFINEMENT; AND (3) AN ANALYSIS OF FELONY ARREST DISPOSITIONS IN FOUR SOUTHERN CALIFORNIA COUNTIES. RESEARCH IN PROGRESS ENCOMPASSES ANOTHER INMATE SURVEY OF BOTH PRISON AND JAIL INMATES FROM THREE STATES, A STUDY OF CHANGES IN PROSECUTION AND SENTENCING OUTCOMES UNDER CALIFORNIA'S DETERMINATE SENTENCING ACT, AND A STUDY OF HOW JUVENILE RECORDS ARE USED IN ADULT CRIMINAL PROCEEDINGS. MAJOR FINDINGS ON RESEARCH COMPLETED AS OF 1979 INDICATE THAT FEW OFFENDERS SPECIALIZE, BUT RATHER ENGAGE IN SEVERAL DIFFERENT CRIME TYPES; INDIVIDUAL CRIME RATES SHOW A MODERATE DECLINE WITH AGE AND SUBSTANTIAL INCREASE WITH PRIOR RECORD; A STRONG RELATIONSHIP EXISTS BETWEEN PRIOR RECORD AND CASE OUTCOMES; AND AT LEAST A 3-PERCENT INCARCERATION INCREASE WOULD BE REQUIRED TO BRING ABOUT A 1-PERCENT DECREASE IN CRIME. SOCIAL AND PSYCHOLOGICAL CORRELATES SHOW THAT IN GENERAL, HIGH-RATE OFFENDERS ARE MORE LIKELY THAN OTHER OFFENDERS TO EXPRESS HEDONISTIC REASONS FOR CRIME, AS OPPOSED TO ECONOMIC DURESS. FINALLY, A NATIONAL SURVEY, COVERING THE ENTIRE SPECTRUM OF CRIMINAL JUSTICE AGENCIES TO DETERMINE HOW THEY COULD COORDINATE THEIR ACTIVITIES WITH CAREER CRIMINAL PROSECUTION PROGRAMS, INDICATES THAT THE POLICE COULD PROVIDE MORE DIRECT ASSISTANCE TO THE PROSECUTOR, CONCENTRATE INVESTIGATION RESOURCES ON SUSPECTED CAREER CRIMINALS, AND UPGRADE THEIR GENERAL CRIME ANALYSIS AND INVESTIGATION EFFORTS. FOOTNOTES AND REFERENCES ARE PROVIDED. (AUTHOR ABSTRACT MODIFIED)