An exciting period in mental and physical health research is beginning, resulting from a paradigm shift from an outdated biomedical reductionism approach to a more comprehensive biopsychosocial model, which emphasizes the unique interactions among biological, psychological, and social factors required to better understand health and illness. This biopsychosocial perspective is important in evaluating the comorbidity of mental and physical health problems. Psychiatric and medical pathologies interface prominently in pain disorders. Important topics in the biopsychosocial approach to comorbid chronic mental and physical health disorders, focusing primarily on pain, are presented. Though this biopsychosocial model has produced dramatic advances in health psychology over the past 2 decades, important challenges to moving the field forward still remain.