In the current debate over the future of the Affordable Care Act (ACA), research evidence on the impact of the law and the effects of health insurance coverage in general is critical. Studies of health insurance expansion over the past decade have demonstrated that coverage expansions can produce significant reductions in mortality—particularly among minorities, those living in poorer areas, and those with chronic conditions potentially treatable with timely medical care. More recent studies of the ACA in particular demonstrate that the law has produced historically large reductions in the uninsured rate, with resulting improvements in access to care, perceived quality of care, and self-reported health. Yet much of the general public and many policy makers remain unaware of this evidence. Researchers and clinicians in academic medicine have a role to play in ensuring that critically important health policy decisions are made using rigorous evidence to best protect the interests of our patients.