William Smith was born in 1862 Jamaica while his Scottish father was working as an engineer on the island.

After finding limited success in New York, he then traveled west and met Andrew Still in Missouri in June 1892.

After investigating Still's claims, Smith agreed to serve as the first anatomy professor at Still's new school, which was opening in September, and Smith helped in the founding of several other osteopathic institutions.

In 1900 Smith briefly served as president of the Atlantic School of Osteopathy in Pennsylvania.

In 1912 he returned to Scotland after several unsuccessful attempts at starting a practice in the United States.