DAWN is a national surveillance system that monitors drug-related morbidity and mortality by collecting data from a scientific sample of hospital emergency departments and a set of medical examiners and coroners from across the United States, with concentrations in selected metropolitan areas. This report presents DAWN data submitted for 2002 by 29 hospitals in the Los Angeles metropolitan area. Of the 2.7 million visits to Los Angeles area ED's in 2002, approximately 1 percent (24,592) involved drug abuse. During 2002, the most common drugs involved in ED visits were alcohol in combination with other drugs, cocaine, marijuana, heroin, benzodiazepines, and narcotic analgesics (pain relievers). Between 1995 and 2002, cocaine-related ED visits in Los Angeles increased 77 percent, from 61 to 108 visits per 100,000 population. Almost three-fourths of cocaine-related ED visits also involved other drugs. Over the same period, marijuana-related ED visits more than tripled, from 21 to 64 visits per 100,000 population. Most (85 percent) of ED visits that involved marijuana were in combination with other drugs. Heroin-related ED visits decreased 21 percent between 2000 and 2002; approximately half of heroin-related ED visits also involved other drugs. From 1995 to 2002, drug-related ED visits that involved benzodiazepines have been relatively stable. In 2002, narcotic pain relievers and benzodiazepines were each as frequent as heroin in drug-related ED visits. Drug-related ED visits in Los Angeles for 2002 are compared with 20 other DAWN metropolitan areas for cocaine, marijuana, heroin, and benzodiazepines. 9 figures