We examined reports from three surveillance systems of 587 acute releases of hazardous materials in 1986. These releases resulted in at least 115 deaths, 2,254 injuries, and 111 evacuations. Only eight (1 percent) of the 587 events were common to all three systems. Estimates of the public health consequences of hazardous materials releases could be improved by enforcing existing laws, modifying report forms, and validating collected information.