Sector Wide Approaches (SWAps) are an approach to aid management that aim to support recipient government leadership. Health aid has grown rapidly in the past 20 years and in this time SWAps have become an important health aid delivery approach. However, the empirical evidence is that the performance of health SWAps is, at best, mixed. Outcome and impact benefits of health SWAps are inconclusive, and overall process level performance is poor. The key insight offered by this paper is that a divergence has developed between the underlying theory of change of health SWAps, and their implementation. The paper argues the theory of change underlying SWAps is highly consistent with effective aid, however the practice is not. Health SWAps have been characterised by cumbersome architecture that is partially implemented and used, and which does not facilitate government ownership and commitment to indigenous institutional development.