"Hispanics" encompass a population that includes several ethnic subgroups from different countries of origin, including Mexico, Puerto Rico, Cuba, and a host of Central- and South-American countries. In 2003, Hispanics composed 14 percent of the U.S. population. Substance abuse treatment admissions reported to the Treatment Episode Data Set (TEDS) for 2003 involved Hispanics. TEDS is an annual compilation of data on the demographic characteristics and substance abuse problems of those admitted to substance abuse treatment. In 2003, the most common primary substances of abuse among Hispanic admissions were alcohol (36 percent), opiates (28 percent), and marijuana (15 percent). Hispanic admissions were more likely to report primary opiate abuse than non-Hispanic admissions (28 percent compared with 16 percent), and Hispanics were less likely to report primary alcohol abuse (36 percent compared with 43 percent). Daily use of the primary substance in the month prior to admission was reported by 46 percent of Hispanic admissions compared with 42 percent of non-Hispanic admissions. Hispanic admissions were 78 percent male and 22 percent female compared with 68 percent male and 32 percent female among non-Hispanic admissions. Among Hispanic male admissions, alcohol abuse was the most common primary substance abuse problem (39 percent). On average, Hispanic admissions were slightly younger than non-Hispanics at admission (33 compared with 34 years old). Puerto Rican admissions most often reported opiates as the primary substance of abuse, and other Hispanic admissions most often reported alcohol abuse. 3 figures and 6 notes