The announcement that Justice Anthony Kennedy will retire from the US Supreme Court has created deep uncertainty about a range of issues related to health. Kennedy was regarded as a swing vote on the court—while he generally sided with the court’s conservative wing, he famously joined with progressive opinion on the issues of abortion and LGBT rights. His successor will likely make decisions about these and many other issues, including the economy, voting rights, the environment, and the basic ground rules of our politics, all of which will have ramifications for health.