The Strike Force program in Bergen County was designed to provide enforcement and deterrence through random roadside checkpoints. The DWI Task Force and SOBER (Stay Off the Bottle, Enjoy the Road) programs were both educational and community support programs. The analysis focused on single-vehicle crashes and nonpedestrian fatalities involving a motor vehicle and taking place between 6 p.m. and 5:59 a.m. The road blocks were associated with a drop of 10-15 percent in the single vehicle nighttime crash rate and showed a relatively stable effect over time. The DWI Task Force was associated with a 6-10 percent total decline in the crash rate and declining impact over time. SOBER was associated with a small effect in the first year and little or no effect thereafter. Findings showed that the checkpoint program reduces single-vehicle nighttime crashes, although the program's effectiveness may depend partly on the publicity that accompanies its implementation. In addition, judicious and perhaps sporadic use of publicity and education campaigns may have temporary beneficial impacts. Tables and 11 references. (Author abstract modified)