Highlights from this report include: for the period July - September 1978, there were 28,956 drug-abuse episodes reported at emergency rooms involved in the Drug Abuse Warning Network (DAWN) Project that involved 44,144 drug mentions; and during the period April through June 1978, there were 769 drug-abuse episodes reported by medical examiners included in the DAWN network that involved 1,463 drug mentions. For the emergency room drug-abuse episodes, the leading drug of mention was tranquilizers (23 percent), followed by alcohol-in-combination (12 percent), non-narcotic analgesics (9.8 percent), and non-barbiturate sedatives (8.2 percent). The five drugs most often mentioned by medical examiners in connection with drug-related deaths for the period covered were alcohol-in-combination, heroin/morphine, d-propoxyphene, secobarbital, and diazepam. This report presents data on drug-abuse episodes and drug mentions collected through DAWN for the period July through September, 1978. Data were obtained from 778 emergency rooms and 111 medical examiners located within the 24 primary SMSA (standard metropolitan statistical area) cities and 3 additional cities from across the country. The report presents information for the DAWN network as a whole, and for each individual SMSA. DAWN is a large-scale, ongoing drug abuse collection system with several objectives: identifying substances associated with drug abuse episodes; monitoring drug abuse patterns and trends; assessing health hazards associated with drug abuse; and providing data for national, State, and local drug abuse policy and program planning. Tables and figures