My work broadly aims to generate evidence to support the advancement of public health practices and policies that improve behavioral health and increase equity for disadvantaged groups in the U.S. Using large administrative databases and national surveys, I analyze patterns of drug use and behavioral health care, the relationship with population and patient outcomes, and the influence of social and structural factors on prevention and treatment of mental health and substance use problems. Current studies examine care access and quality in public insurance programs covering low-income Americans and individuals with disabilities, with a focus on treatment disparities across racial and ethnic groups.