Several papers use survey data from national samples to demonstrate that significant drug use is occurring among employed people. Approximately one in nine employed people and one in five of those ages 18 to 34 report current use of marijuana. Rates are lower for professional and managerial personnel compared to skilled and semi-skilled labor categories. Data are also coming from workplace drug testing programs. The papers on the impacts of drug use on performance and productivity show demonstrable differences between users and nonusers in some measures of work performance, although the causative factors are unknown. Industry responses include written policies, employee assistance programs, and drug testing programs. Other papers focus on the role of the supervisor in workplace substance abuse programs, legal and political issues, and research needs. Figures, tables, and chapter references lists.