In the early twentieth century, blood transfusions were rare, risky, and difficult to perform despite their lifesaving potential. Everything changed in 1937 at Chicago's Cook County Hospital, where physician Bernard Fantus, MD, established the world's first blood bank. Learn how this groundbreaking innovation revolutionized emergency medicine, transformed hospitals around the globe, and saved countless lives. This fascinating story of scientific discovery and medical history highlights Chicago's pivotal role in one of medicine's most important advances.