This report explores the development of implementation strategies used to enhance the programme “Assessment for Learning – 2010-2014” in Norwegian schools. Norway’s educational governance is highly decentralised, with 428 municipalities and 19 counties responsible for implementing education activities, organising and operating school services, allocating resources and ensuring quality improvement and development of their schools. This case study is based on56 interviews with 98 key actors and stakeholders in the Norwegian education system, as well as analysis of key policy and legal documents and a range of media articles. Key findings include the importance of clear communication between governance levels and a high degree of trust between stakeholders; the need for a clear understanding of programme goals, the role of learning networks between schools to aid the exchange of knowledge and provide peer support during the implementation process. Innovative forms of capacity building were of particular importance for the smaller municipalities, who reported being overextended by the continual stream of policy changes and struggling with prioritising activities. The case study also provides a series of recommendations for improvement.