For each major type of data, definitions, data collection techniques, and factors affecting data and related issues also are examined. Data indicate that from 1982 to 1983, California Crime Index offenses per 100,000 population decreased 7.6 percent overall, with a 5.2 percent decrease in violent crimes and an 8.4 percent decrease in property crimes. In this period, total arrests decreased .9 percent. Decreases were 4.8, .4, and 4.5 percent for felony, misdemeanor, and status offense arrests, respectively. Of 201,158 adult felony arrest dispositions in 1983, releases accounted for 27.9 percent, dismissals and acquittals for 16.5 percent, and convictions for 55.5 percent. The total number of adults under supervision increased 12.4 percent from 1982 to 1983, with the greater increase in adults under State supervision as opposed to local supervision. New referrals to the probation departments of the juvenile justice system decreased 7.4 percent, juveniles on caseload status increased 10.9 percent, and juveniles in county probation detention facilities increased .5 percent. Total criminal justice agency expenditures increased 8.1 percent, to $5.4 billion. Expenditures by law enforcement agencies increased 8.8 percent. Total criminal justice agency authorized full-time personnel increased 2 percent; law enforcement personnel increased 1.8 percent. Additional data are provided in 58 tables, including the number and disposition of citizen complaints against police. Appendixes present a discussion of known data limitations and a criminal justice glossary.