Six years after the implementation of regulations reducing the work hours of residents, it appears clear that patient outcomes have neither improved nor worsened. This study of mortality in 40 intensive care units found that mortality decreased in all hospitals after introduction of duty hour regulations, with no difference between teaching and non-teaching hospitals. Therefore, the authors interpret their findings as confirming prior work demonstrating no impact on outcomes. However, the effect of reduced duty hours on patient safety and education remains unclear. Further changes in duty hour regulations are expected, after the recent publication of an Institute of Medicine report that recommended reducing shift length and increasing supervision of residents.