Complex health care interventions need a theoretical basis underpinning their implementation (Campbell et al. 2000).
•The NPS has created a nationally co- ordinated program with an articulated and agreed vision (Emanual 2002)
•The program developed from an evidence-based approach and incorporated a partnership ‘model’ with local agencies such as the divisions of general practice to allow the effective and efficient use of scarce resources (Fleisher et al. 1998; Wensing et al. 1998).
•NPS provided technical information, standardized materials, capacity build- ing and the vision to improve use of medicines that has been crucial to the sustainability of a national program (Fleisher et al. 1998).