The discussion is based on a literature review, a telephone survey of 14 administrators of electronic monitoring programs during April-May 1987, and reports from presenters at a 1987 seminar on electronic monitoring. Electronic monitoring is used mostly to alleviate jail and prison crowding from pretrial through parole. Both of the two basic types of systems used involve offenders' wearing an electronic device on the wrist or ankle. One system uses random calling and a beeper alert system which notifies field staff when a violation has occurred. The other system uses radio frequency to emit a constant radio signal. Both systems have advantages and disadvantages. Offenders placed under electronic monitoring have included misdemeanants, felons, and both presentenced and sentenced offenders. They have been convicted of drunk driving, property offenses, minor drug and alcohol offenses, and other nonviolent offenses. Operational issues include whether 24-hour supervision is necessary, staffing requirements, the supervision level required, the period of monitoring, whether it is cost effective, and whether it can be use on pretrial detainees and juvenile offenders. There are potential legal problems and abuses, but overall the results of electronic monitoring have been promising. Examples of its uses are cited. A 13-item selected bibliography.