Background: World-wide, there is growing universal health coverage (UHC) enthusiasm. The South African government began piloting policies aimed at achieving UHC in 2012. These UHC policies have been and are being rolled out in the ten selected pilot districts. Our study explored policy implementation experiences of 71 actors involved in UHC policy implementation, in one South African pilot district using the Contextual Interaction Theory (CIT) lens.Method: Our study applied a two-actor deductive theory of implementation, Contextual Interaction Theory (CIT) to analyse 71 key informant interviews from one National Health Insurance (NHI) pilot district in South Africa. The theory uses motivation, information, power, resources and the interaction of these to explain implementation experiences and outcomes. The research question centred on the utility of CIT tenets in explaining the observed implementation experiences of actors and outcomes particularly policy- practice gaps.Results: All CIT central tenets (information, motivation, power, resources and interactions) were alluded to by actors in their policy implementation experiences, a lack or presence of these tenets were explained as either a facilitator or barrier to policy implementation. This theory was found as very useful in explaining policy implementation experiences of both policy makers and facilitators. Conclusion: A central tenet that was present in this context but not fully captured by CIT was leadership. Leadership interactions were revealed as critical for policy implementation, hence we propose the inclusion of leadership interactions to the current CIT central tenets, to become motivation, information, power, resources, leadership and interactions of all these.