This study explored the use of mental health services by Asian Americans and other ethnic populations (N=104,773) in California. The authors used linear regression analyses to assess the role of ethnicity and diagnosis in predicting six-month use of services. East Asians used more services than Southeast Asians, Filipinos, other Asians, Caucasians, African Americans, Latinos, and Native Americans, even when severity of illness was taken into account. The findings suggest that aggregating Asian subpopulations into a single group in services research is no longer appropriate. Attention needs to be placed on the needs of Southeast Asians and other Asians, whose service use patterns approximate those of the traditionally most underserved groups, African Americans and Latinos.