Data were first collected from a representative sample of all felony cases disposed in 1979 and reported to the Wisconsin Court Information System; data were then collected on all new felony and misdemeanor offenses committed by defendants in the original sample. The report describes characteristics of the original 502 cases studied, focusing on charges filed, characteristics and predisposition release status of defendants, and case processing time. It then examines the frequency and type of new felony offenses committed by defendants in the sample prior to disposition of their original charges. Data indicate that most defendants were young, male, and white. A total of 78 percent of defendants were released prior to the disposition of their cases, although 22.8 percent of those released spent some time in custody. The original cases were disposed within about 127 days of their initial court appearance, with 91 days as the median time to disposition. Defendants in 23 of the 502 original cases were arrested for 25 predisposition felony offenses. Of the 25 new offenses, the major charge in 20 cases was a property crime. Despite the fact that most new felonies occurred relatively early in the processing of the original case, such original cases took substantially longer to process than others in the sample. This suggests that early new offenses may prolong a pending felony case. Footnotes and tables are included.