The article begins with a general discussion of electronic monitoring, including what it is, its origins, and some of the practical, ethical, and legal issues associated with its use. Electronic monitoring is often referred to as "house arrest" and serves to keep offenders in the community while restricting their movement. It is a form of intensive supervision that usually requires an electronic device that is attached to the offender's body for tracking. These devices allow correctional staff to monitor offenders' movements and determine whether they have violated their restrictions. The measurement of the effectiveness of electronic monitoring as a tool in supervising offenders and protecting the public may focus on cost savings compared with incarceration and the degree to which persons who would otherwise be incarcerated are diverted to electronic monitoring. Outcome effectiveness generally refers to whether electronic monitoring is serving some of the more explicit functions of corrections; namely, whether it deters, incapacitates, or punishes. Because of the limited research pertinent to the effectiveness of electronic monitoring, it cannot be determined whether electronic monitoring is an effective alternative to incarceration. What is known, however, is that the public supports it as an increased form of control over offenders in the community and that the public's increasing fear of crime demands a "control orientation" in community corrections. Regardless of whether it saves money, reduces recidivism, or mitigates prison crowding, electronic monitoring is proliferating and will continue to evolve as a popular correctional alternative. 51 references