Although there are thousands of published recommendations in anesthesiology clinical practice guidelines, the extent to which these are supported by high levels of evidence is not known. In this issue of Anesthesiology, Laserna et al. present a systematic review of anesthesia evidence-based recommendations from the major North American and European anesthesiology societies, mapping the level of evidence supporting current recommendations. In an accompanying editorial, Neuman and Apfelbaum discuss the strengths and limitations of practice guidelines and their role in current clinical practice. Cover Illustration: A. Johnson, Vivo Visuals. Photo: J. P. Rathmell.

  • Laserna et al.: Levels of Evidence Supporting the North American and European Perioperative Care Guidelines for Anesthesiologists between 2010 and 2020: A Systematic Review, p. 31

  • Neuman and Apfelbaum: Clinical Practice Guidelines in Anesthesiology: Adjusting Our Expectations, p. 9