A skilled workforce is critical to the delivery of quality school age care services. A strategy called Core Knowledge and Competency (CKC) Framework was designed to build the skills and knowledge of after school care educators as they provided before and after school programs in Queensland, Australia. The strategy was to help educators meet the Australian National Quality Standard for Early Childhood Education and Care and School Age Care (National Quality Standards) (NQS). This article describes the use of realist evaluation principles to examine the implementation of this strategy. Improvements to the quality of the workforce were reported including less staff turnover, increased capacity and competence of educators which would result in enhanced outcomes for children. However the implementation of the strategy relied on highly competent leaders within the services.