Highlights from this report include: for the period May 1977 through April 1977, there were 168,816 drug-abuse episodes reported at medical facilities involved in the Drug Abuse Warning Network (DAWN) Project that involved 245,551 drug mentions. Of the 168,816 drug-abuse episodes, 72 percent were reported in emergency rooms, 2 percent were reported by medical examiners, and 30 percent were reported at crisis centers. Analysis of drug-abuse patients at emergency rooms found that 41 percent were male and 59 percent were female; 69 percent were White, 27 percent were Black, and 4 percent were other races; and 44 percent were between the ages of 20-29 years. This report presents data on drug-abuse episodes and drug mentions collected through DAWN for the period May 1976 through April 1977, the fifth phase of the DAWN project. For this report, data were obtained from 796 hospital emergency rooms, 112 medical examiners, and 42 crisis centers, located in 24 SMSAs (standard metropolitan statistical areas) and 3 additional cities from across the country. 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