No U.S. Supreme Court decision has directly tested the constitutionality of sobriety checkpoints. However, lower court rulings have established the need for procedural safeguards. Jurisdictions considering using safeguards must first consider whether State laws authorize their use and the use of preliminary breath alcohol tests. Written directives should cover all aspects of checkpoint operation. Determination of the checkpoint site should rest on the significance of the drunk driving problem in the area and the physical suitability of the site. Extensive planning should precede the establishment of a checkpoint. Lengthy stops are impermissible. Contacts with motorists can vary from 20 seconds to more than 1 minute. If possible, police officers should stop all vehicles. Otherwise, systematic sampling using a predetermined procedure is necessary. A field supervisor must ensure adherence to guidelines. Checkpoints should receive three types of evaluation: administrative evaluation, impact analysis, and analysis of public reaction. Description of procedures for stopping and checking motorist and three multiple-choice questions and answers based on the text.