In 2012, Consumers Reports and the American Board of Internal Medicine Foundation launched the Choosing Wisely campaign. This initiative, which attracts media attention, assists physicians, nurses, pharmacists, and medical laboratory scientists identify overused diagnostic tests and treatments. Over 70 medical specialty societies now collaborate with CR and ABIM to generate diagnostic and treatment guidelines. These include the American Association for Clinical Laboratory Science, the American Association of Blood Banks, the American Society for Hematology, and the American Society for Clinical Pathology, who focus on laboratory test utilization and the blood product administration, CR and ABIM, with support from the Robert Wood Johnson Foundation, support local "Champtions" who develop means for applying Choosing Wisely recommendations. We examine the effects of Choosing Wisely on medical laboratory test ordering and interpretation.