Hematopoietic cell transplantation (HCT) is the treatment of choice for many hematologic malignancies such as acute leukemia and lymphoma. During the past four decades, there have been tremendous advances in HCT, contributing to a growing number of long-term survivors of living in the U.S. today. However, these survivors are at risk for severe and life-threatening complications that can significantly impact quantity and quality of survival. Among these survivors, the risk of cardiovascular diseases (CVDs) such as heart failure, stroke, or heart attacks is nearly four times greater than would be expected for the general population, and five-year overall survival in patients with CVD is <50%. As such, it is important to develop reliable accurate screening strategies for early detection of CVD, so that proper interventions can be initiated to mitigate the long-term risk and devastating consequences of CVD. We will perform a comprehensive assessment of cardiovascular health in long-term survivors of HCT, using an established and validated tool (cardiopulmonary exercise testing) that is highly prognostic for CVD and premature mortality in individuals with and without cancer. In addition, HCT survivors will undergo comprehensive organ-specific (cardiac, pulmonary, musculoskeletal) evaluations, to better understand the mechanisms which contribute to impairment of cardiovascular health after HCT, so that targeted interventions can be developed to minimize long-term CVD risk.