The fourth Commonwealth Fund Scorecard on State Health System Performance tells a story that is both familiar and new. Echoing the past three State Scorecards, the 2015 edition finds extensive variation among states in people's ability to access care when they need it, the quality of care they receive, and their likelihood of living a long and healthy life. However, this Scorecard—the first to measure the effects of the Affordable Care Act's 2014 coverage expansions—also finds broad-based improvements. On most of the 42 indicators, more states improved than worsened. By tracking performance measures across states, this Scorecard can help policymakers, health system leaders, and the public identify opportunities and set goals for improvement. The 50 states and the District of Columbia are measured and ranked on 42 indicators grouped into five domains: access and affordability, prevention and treatment, avoidable hospital use and cost, healthy lives, and equity. Individual indicators measure things like rates of children or adults who are uninsured, hospital patients who get information about how to handle their recovery at home, hospital admissions for children with asthma, and breast and colorectal cancer deaths, among many others.