A variety of equipment was procured during the program in an effort to improve the police department's ability to identify, apprehend, and provide adequate evidence for the prosecution of drunken drivers. Additional patrol cars, breath testing equipment, and booking station vans were among the equipment purchased. The selection and training of police officers to participate in ASAP activities were also key factors in the success realized by the San Antonio ASAP. Patrol strategy was conducted on a purely overtime voluntary basis, and all ASAP patrol officers underwent special training in the identification, apprehension, and processing of offenders. Selective patrol operations were funded on an overtime basis nightly throughout the program's 5 years. A number of patrol strategies were introduced, conducted, and evaluated to identify the most effective methods of using the available manpower and equipment. The use of selective patrols resulted in a five-fold increase in drunken drivers apprehended during the first year and a four-fold annual increase thereafter. Evaluation findings showed that early and continued support of police officials is essential to the success of enforcement countermeasures. Special police training in identifying, apprehending, and processing drunken drivers is a major factor in increasing the number and improving the quality of arrests, as is the use of special overtime forces during nighttime hours. To be effective, ASAP must provide for increased cooperation between police departments and the courts, and must have firm community support. A map and tabular data are included.