This article focuses on the outsourcing of NPD in medium sized firms and especially the decisions connected to outsourcing. Although the framework is probably also useful for small and large firms, the three empirical studies the results explored samples of medium sized firms. NPD is a knowledge intensive activity that requires the ability to handle uncertainties and it is very dependent on the individuals involved in the process. In this way it differs from production, which (especially when producing standard items on a large scale) is easier to control, monitor and to evaluate the costs. Outsourcing can lead to advantages in form of lower costs, access to knowledge or other resources, as well as access to markets, but it can also result in a knowledge drain, lower motivation among in-house staff, or an increased level of dependency on external organizations. A decision framework is presented that describe the decisions process when outsourcing NPD.