William Alexander Hammond (1828-1900) was an American neurologist and the 11th Surgeon General of the U.S. Army (1862-1864). In addition to his pioneering work in neurology and his military service, especially during the Civil War, he founded the Army Medical Museum (now called the National Museum of Health and Medicine), co-founded the American Neurological Association and gave his name to Hammond's disease, a type of athetosis which he was the first to describe in 1871. He was also an amateur naturalist, and a species of spadefoot toad (Spea hammondii) was named in his honor.