Clarke initially treated his patients under a tree before going on to establish Kiwoko Hospital which, as of March 2015, maintained a nurses training school, a laboratory technician training school, a large community health programme, a neonatal ICU, and full general hospital facilities.
The hospital has state-of-the-art facilities including specialties such as obstetrics and gynecology, pediatrics, and plastic surgery.
[4] Clarke also writes a weekly column in The New Vision, Uganda's biggest daily, and has penned two books entitled The Man with the Key Has Gone and How Deep Is This Pothole.
He has further projects in Juba, South Sudan and in Zanzibar, Tanzania where his family built, owns, and operates a boutique hotel.
Their oldest son Sean oversees the approximately 12 clinics that his father owns in Uganda.
[2] In November 2010, Clarke entered Ugandan politics by securing nomination, as an independent candidate, to contest for the chairmanship of Makindye Division, one of the five divisions of the Kampala Capital City Authority, the governing body of Uganda's capital city of Kampala.