The analysis indicated that in 2000, approximately 4 percent of the global health burden was related to the use of alcohol and tobacco while another 0.8 percent of the global health burden was related to the use of illicit drugs. Tobacco use was the most significant health risk factors for developed countries and had the highest mortality risk of all substance use categories included in the analysis, particularly among elderly individuals. On the other hand, alcohol use was the most significant of all risk factors in emerging economies and tended to impact younger individuals in comparison to tobacco. Evidence indicates that the global burden from psychoactive substances will increase in coming years due to two main factors: (1) the increased exposure of legal substances, particularly in Southeast Asia and China; and (2) the relative proportion in the total burden of diseases associated with substance use, including chronic diseases, injuries, HIV, and hepatitis, are expected to increase. The authors argue that a substantial portion of the substance-related global health burden could be eased with the implementation of effective interventions. Data were drawn from the comparative risk analysis (CRA) found in the Global Burden of Disease (GBD) 2000 study, which quantified the burden of disease from global substance use. The limitations of the GBD 2000 study are noted and include the measurement used for exposure to drug-related risk and the degree to which the risk estimates can be generalized. Tables, figures, references