Founder of the Boy's Brigade. Born in Thurso (Caithness), Smith moved to Glasgow at the age of 15 to join his uncle's business. Religion played an important part in Smith's life and while teaching in a Sunday School, he realised there was a need for an organisation based on Christian principles to provide focus for his boys. Taking these principles, together with the discipline learned during his time serving as a soldier in the 1st Lanarkshire Rifle Volunteers, he founded the Boy's Brigade in 1883. By 1887, he was full-time Secretary of the Brigade and he was knighted for his services in 1909.
Smith died following a Boy's Brigade Rally in London's Albert Hall and is buried in Glasgow. His son succeeded him as Brigade Secretary.