A 5-year research effort (1973-1977) sponsored by the National Institute of Law Enforcement and Criminal Justice outlined alternatives to jail -- diversion, pretrial release, and sentencing options. The action program tested the systemwide planning approach to alleviate jail overcrowding over 4 years at 21 sites. A 3-year evaluation showed that the project sites did a better job than control sites in screening pretrial detainees and developing alternatives that saved thousands of jail days. Also, standards were developed for local detention facilities, covering such topics as administration, management, and inmate supervision. A systemwide jail policy board should be created and should review all the data on the causes of jail overcrowding and on proposed solutions. A screening system should be developed for defendant classification and implemented by a responsible unit of State government. At the local level, the core program includes a planning effort followed by an implementation project; Federal agencies provide training, technical assistance, and program manuals for State and local teams. Successful implementation of the jail overcrowding program has fostered benefits such as interagency cooperation in planning and implementing the program and early case screening. Functions and agencies involved, State, local, and Federal contacts, and sources of technical assistance are listed; a 10-item bibliography is included.