Despite a decade of efforts to improve care for patients with acute myocardial infarction (AMI) there remains substantial variation across hospitals in patient mortality rates after AMI. The risk-adjusted 30 day mortality rates of hospitals in 2003 ranged from 11% to 23%, more than a two-fold difference. Although patient survival is a fundamental goal of the hospitalization, we know little about what distinguishes hospitals with lower risk-adjusted short-term mortality rates. A substantial body of health care organizational theory posits that hospital structures, processes, and internal environments may influence hospital operational and financial outcomes;however, we have less empirical evidence concerning their influence on clinical outcomes;such as risk-adjusted mortality rates, especially among patients with AMI. We will use a mixed methods approach to: 1) generate hypotheses regarding hospital-specific efforts (characterized as enabling structures, processes of care, and hospital internal environments) that may be associated with hospital risk-adjusted 30 day mortality rates for patients with AMI;and 2) determine the hospital effort that are statistically associated with hospital risk-adjusted 30 day mortality rates for patients with AMI. This methodology employs qualitative and quantitative research in a complementary fashion to generate and then to test hypotheses. We employ a validated, risk-adjusted mortality model and hierarchical generalized linear models to examine hospital-level variation in risk-adjusted mortality. This risk-adjustment model has been endorsed by the National Quality Forum and slated for use by the Centers for Medicare &Medicaid Services (CMS) as a publicly reported quality indicator in 2007. The lack of evidence about what accounts for hospital-level variation in risk -adjusted mortality rates is a critical gap in our current knowledge about how to improve outcomes. The proposed study will provide the foundation for evidence-based efforts to elevate hospital performance in risk-adjusted 30-day mortality for patients with AMI. We will work on dissemination strategies with CMS, JCAHO, American College of Cardiology (ACC), American Health Association (AHA), the Veteran's Administration (VA), and the VHA.