This report presents information from the 2000 National Household Survey on Drug Abuse (NHSDA) on rates of use, numbers of users, and other measures related to illicit drugs, alcohol, cigarettes, and other forms of tobacco. This report includes separate chapters that summarize the findings of the survey on five topics: use of illicit drugs; use of alcohol; use of tobacco products; initiation of substance use; and prevention-related issues. A final chapter summarizes the results and discusses key findings in relation to other research and survey results. General conclusions from the 2000 NHSDA include: substance use rates were generally level or declining between 1999 and 2000; and use and abuse of licit and illicit substances in the U.S. remains a major problem, affecting a large portion of the population. Appendices give technical details on the survey methodology, discuss other sources of data, and provide references and detailed tabulations of estimates. Tables and text present prevalence measures for the population in terms of both the number of substance users and the rate of substance use for illicit drugs, alcohol, and tobacco products. Tables show estimates of drug use prevalence in the lifetime, past year, and past month. The analysis focuses primarily on past month use, which is also referred to as current use. (Contains approximately 78 references, 87 tables, and 34 figures.)(GCP)