The Offender Based Transaction Statistics (OBTS) consist of data which permit examination of offender characteristics and patterns of court action and case disposition. The data set includes all cases which reached disposition during the calendar year 1980. It provides selected information about offenders and their arrests, prosecutions, and court dispositions. The file contains approximately 35 variables and has a logical record length of 130 characters. There are approximately 188,445 records for California, 7,953 records for Ohio, and 59,191 records for Pennsylvania. Appendixes discuss geographic coverage, tape characteristics, instructions for coding the OBTS data elements, data elements, and condensed records for multiple charges.