Highlights on data on homeless young adults in substance abuse treatment from the 2008 Treatment Episode Data Set (TEDS) include: (1) heroin (26.9 percent) and alcohol (25.0 percent) were the most frequently reported primary substances of abuse among homeless young adult admissions in 2008; (2) homeless young adult admissions were more likely than non-homeless young adult admissions to have had five or more treatment episodes (17.3 versus 6.2 percent); and (3) among homeless young adult admissions, individual/self referrals were the most common source of referral to treatment (41.5 percent. These data highlight the fact that homeless young adults face challenges associated with substance addictions and require treatment tailored to their life situations. Understanding the characteristics of homeless young adults in substance abuse treatment can help public health efforts aimed toward prevention, improving access to treatment, and treatment effectiveness with this population. Data from the TEDS for 2008 can be used to examine homelessness among admissions to substance abuse treatment. 4 figures and 6 notes