The topic of this article is experiences regarding Supplemental Instruction (SI) at two Scandinavian Universities. The purpose is to describe the basis for and implementation of SI programmes at the two universities, and to compare their similarities and differences. Our research questions were as follow: What were the reasons and background for implementing SI? How was the SI programme founded, prioritised, and made visible and more widespread? What type of research and results relating to SI have been put forward? What challenges and success factors have been experienced during the implementation and integration of the SI programme? The study employs a qualitative design, aiming to provide in-depth information about the universities’ implementation and organisation of SI programmes. A case study approach gives us the opportunity to study the SI programmes as a process and activity, since case studies provide the opportunity to explore or describe a phenomenon in context In order to describe the cases, we selected a set of factors to focus on, which included: reasons for introducing and implementing SI, prime advocates, integration and communication, research on SI, and success and challenges. Our results show that the two universities give the same reasons for introducing SI, but differ in their organisation and integration of the SI programme.