Horizon Europe, the 9th framework programme, is the EU’s main instrument for investments in research and innovation for the period 2021–2027. This book presents the results of the impact assessment that underpinned the legislative proposal for the programme, in line with the Commission’s better regulation guidelines. The impact assessment builds on the evidence and lessons learnt from the interim evaluation of the 8th framework programme, Horizon 2020, and the recommendations of the independent high-level group on maximising the impact of EU research and innovation. Horizon Europe is ‘an evolution, not a revolution’, focusing on a few design improvements to further increase openness and impact and EU added value for citizens. The impact assessment therefore identifies the main research and innovation challenges in Europe, outlines the objectives of the future programme and its structure, and provides evidence-based policy and design recommendations for its main features, such as the research and innovation missions, and the European Innovation Council.