The U.S. health care system serves a diverse population, often resulting in significant disparities in delivery and quality of care. Nevertheless, most quality improvement efforts fail to systematically assess diversity and associated disparities. This article describes application of the multimethod assessment process (MAP) for understanding disparities in relation to diversity, cultural competence, and quality improvement in clinical practice. MAP is an innovative quality improvement methodology that integrates quantitative and qualitative techniques and produces a system level understanding of organizations to guide quality improvement interventions. A demonstration project in a primary care practice illustrates the utility of MAP for assessing diversity.