In recent years, established companies have made increasing use of intrapreneurship programs – often in combination with innovation activities – in order to combine the advantages of large companies with the speed of start-ups. However, it remains unclear under what conditions such intrapreneurship endeavours work best. This paper therefore examines the meaning of success in this context and investigates what factors influence the success of such programs. By using a mixed-methods approach that includes a comprehensive literature analysis, an interview study with twelve intrapreneurs from the Fiducia & GAD IT AG, and developed guidelines, the paper outlines the success factors of intrapreneurship programs. Furthermore, the 5 P’s (People, Program, Product, Process, and Place) of successful intrapreneurship programs are classified in a model that builds on the 3-horizons-model of innovation. This model enables recommendations to be given for managers regarding how to contribute to the success of intrapreneurship programs.