The Horizon 2020 Work Programme 2014-15 sets out the funding opportunities under the different parts of the programme; all were published on the Participant Portal. Each part describes the overall objectives, the respective calls, and the topics within each call. Each topic describes the challenge to be addressed, the scope of the activities to be carried out, and the expected impacts to be achieved. Compared with the Seventh Framework Programme (FP7), there are relatively fewer calls and topics. The Work Programme reflects the strong challenge-based approach of Horizon 2020, allowing applicants to have considerable freedom to come up with innovative solutions.