The study of pretrial release practices focuses on four topics: release -- what percentage of defendants are released pending trial and what are the most common types of release; court appearance -- to what extent do released defendants appear for court; pretrial criminality -- during the pretrial period, how many defendants are rearrested, and of those, how many are convicted; and the impact of pretrial release programs -- to what extent do pretrial release programs affect release decisions. Eight jurisdictions in Maryland; Florida; Washington, D.C.; Kentucky; Arizona; and California were selected for detailed analysis of release practices and outcomes. Sites were chosen to reflect geographic dispersion, a wide range of release types, and broad eligibility for program participation. The procedures for pretrial release decisions were studied. Analysis identified the major steps in the pretrial release process and the most important organizations and persons involved in that process. Interviews were conducted with program staff, judges, prosecuting and defense attorneys, law enforcement officers, bondsmen, and others involved with pretrial release matters. Publications dealing with release practices in each jurisdiction were reviewed. A sample of defendants was studied from arrest to final case disposition and sentencing. Existing records were used to collect extensive data on defendants' backgrounds, release decisions, program involvement, case outcomes, court appearances, and pretrial arrests. The data are maintained in two formats: a card-image file and an OSIRIS data set.