This paper provides a rationale for, and overview of, procedures used to develop the National Latino and Asian American Study (NLAAS). The NLAAS is nationally representative community household survey that estimates the prevalence of mental disorders and rates of mental health service utilization by Latinos and Asian Americans in the US. The central aims of the NLAAS are to: 1) describe the lifetime and 12-month prevalence of psychiatric disorders and the rates of mental health services use for Latino and Asian American populations using nationwide representative samples of Latinos and Asian Americans, 2) assess the associations among social position, environmental context, and psychosocial factors with the prevalence of psychiatric disorders and utilization rates of mental health services, and 3) compare the lifetime and 12-month prevalence of psychiatric disorders, and utilization of mental health services of Latinos and Asian Americans with national representative samples of non-Latino whites (from the National Comorbidity Study-Replication) (NCS-R) and African Americans (from the National Survey of American Life) (NSAL). This paper presents new concepts and methods utilized in the development of the NLAAS to capture and investigate ethnic, cultural and environmental considerations that are often ignored in mental health research. Copyright © 2004 Whurr Publishers Ltd.