Comprehensive medical and psychosocial services are essential to quality addiction treatment, but their availability declined in the 1980s. To determine whether this downward trend in the availability of comprehensive services continued in the 1990s, we analyzed data from a national panel study of outpatient substance abuse treatment units in 1990, 1995, and 2000. Response rates were greater than 85%. Regarding the availability of comprehensive services, including physical examinations, routine medical care, mental health services, financial counseling and employment counseling, administrators reported whether any substance abuse treatment client received the service in the past year. With the exception of physical examinations, whose reported availability increased from 1990 to 1995, and financial counseling, whose reported availability decreased during the same time, the reported availability of comprehensive services changed little during the 1990s. These findings highlight the continuing need to monitor access to comprehensive services and other quality markers in addiction treatment over time.