The FUNZOKenya Project, led by IntraHealth International and funded by the President’s Emergency Plan for AIDS Relief (PEPFAR) through USAID, scaled up access to in-service training (IST) for practicing health workers through eight regional training hubs. The project defines a regional training hub as a network of medical training institutions, hospitals that serve as sites for practicum training, and health service delivery stakeholders such as the Ministry of Health (MOH) in a defined geographic location. This technical brief provides an overview of the approach and results.