At the Barcelona Meeting in March 2002, the EU member-states agreed upon a common policy goal to increase expenditures for research and development to 3% of GDP by 2010. In 2005 this target was also adopted by the Norwegian Government. This thesis is a case study of how and why the 3% objective became a goal in Norwegian research and development (R&D) policy. The adoption of the EU target is considered a case of policy diffusion through Europeanisation. A combination of features from theories used in Science and Technology Studies and Political Science is employed to show how different approaches to innovation and diffusion can help explain policy transfer from the EU to the national level. Furthermore, the combination of theories is used to analyse different actors and arguments involved in the diffusion process. The arguments were divided into interest-based, idea-based, and rule-based claims according to the motivations and mechanisms underlying them. Concluding remarks drawn from the study indicate that the adoption of the 3% target into Norwegian R&D policy was indeed a result of policy diffusion. Furthermore, the case points out how the identification of actors’ interest-based, idea-based, and rule-based arguments can be vital for understanding the process leading to the transfer of this EU policy goal. However, while the combination of theories of diffusion and innovation are useful for explaining the Norwegian adoption of the 3% objective, its explanatory power is substantially reduced when trying to assess the implementation, or lack of implementation of this R&D policy goal.