Dillon's program of research addresses health disparities and mental health issues affecting racial, ethnic and sexual minority groups in the United States. He aims to promote culturally informed psychosocial interventions. His principal research themes are (a) elucidating cultural and social determinants of substance use disorders and HIV risk behaviors, (b) developing culturally relevant and valid psychosocial measures and (c) promoting multicultural competent counseling practice and education. In his featured article, Dillon reviews a theorized link between Latino immigrants' experience of acculturative stress and declines in family cohesion from pre- to post-immigration contexts. Implications for health services for recent Latino immigrants are also addressed.