It has long been recognized that reduced lung function is a major risk factor for cardiac death. It has also become clear that cardiac events are the major cause of death for patients with chronic obstructive pulmonary disease (COPD) with all stages of disease. These associations could be from shared risk factors, most notably cigarette smoking. However, there are mechanistic and physiologic relationships that could account for these associations. This raises the possibility that treatment of COPD could benefit cardiac risks. Despite this, the monitoring of lung function in cardiac patients is not routine. Neither is optimization of lung function, although it may greatly benefit exercise training designed to minimize cardiac risks and symptoms. Conversely, many patients with COPD are at greater risk for cardiac disease than may be recognized, because their COPD is often undiagnosed. Recognition of increased risk could impact the aggressiveness with which other risk factors, hypertension, and hypercholesterolemia are managed. Finally, the interactions between cardiac and pulmonary disease have important implications for the development of novel therapies. It is plausible that treatment of pulmonary inflammation characteristic of COPD will alter cardiac risk. Such an approach would offer a novel approach for the development of treatments for these common conditions.