Close calls (sometimes called near misses) pose unique challenges and opportunities when it comes to learning from mistakes. Because they are less dramatic than errors that lead to harm, they tend to be ignored in most institutional reporting systems. With a foreword by safety pioneer James Reason, this multiauthored book makes the case that close calls—which are significantly more common than true adverse events—can provide a unique window into an organization's safety hazards. Moreover, because there is less fear about liability and less shame associated with close calls, they may be easier for clinicians to talk about and learn from than true adverse events. By providing case studies from a variety of areas of medicine, this book illustrates the important role of close call reporting, education, and analysis in a robust safety program.