Study data came from official reports and statistics, newspaper clippings obtained from a national press clipping service, and telephone interviews with corrections officials. The study focused on State prisons and not on local correctional facilities. The two main types of intake controls were the use of sentencing guidelines, as exemplified by Minnesota's practice, and the use of alternatives to incarceration as practiced in Georgia. Methods of increasing prison capacity include the construction of additional prison space, the use of county jails to house inmates, provision of temporary housing, and renovation and conversion of existing buildings into prisons. Techniques for moving prisoners through the system more quickly are also termed release valves. They are illustrated by Michigan's sentence rollback law, the liberal use of good time as once used by Illinois, the use of discretion by the Georgia Parole Board, and Alabama's Supervised Intensive Restitution Program. A total of 70 footnotes are included.