Thomas Ogunleye joined the College of Medicine, University of Lagos after his NYSC in 1975. He eventually left the College of Medicine in 1990 when he immigrated to the USA. In between this period, he completed part of his doctoral program at the University of Wisconsin.
He also had a two year tenor with NASA in Houston under the auspices of National Science Foundation Fellowship.
Tom worked with Regional Cancer Treatment Centre in San Angelo, Texas (1990-1995). Later, he moved to Austin to join The Austin Cancer Center (1995-2009). In 2009 he started Pinnacle Radiological Physics services, his own private consulting firm.