In this issue of JAMA, Shrank and colleagues report a thorough review of studies published over the past decade to provide updated estimates on the proportion of US health care spending that is wasteful, defined in 6 broad categories: failure of care delivery, failure of care coordination, overtreatment or low-value care, pricing failure, fraud and abuse, and administrative complexity.1 The authors estimate total annual waste to be $760 billion to $935 billion—smaller as a share of total spending than previous estimates, yet clearly showing that a gulf remains between the current efficiency in the US health care system and what may be possible. But the authors go further than previous studies to assess evidence on how much of this theoretical gulf could potentially be closed, and they conclude that approximately a quarter of that total ($190 billion to $286 billion) could be eliminated if evidence-based strategies to reduce waste were scaled nationally.