Background: Ex ante impact assessment has become a fundamental tool for effective program management, and thus, a compulsory task when establishing a new program in the European Union (EU). Objetive: This article aims to analyze benefits from ex ante impact assessment, methodologies followed, and difficulties encountered. This is done through the case study on the rural development programs (RDPs) in the EU. Results regarding methodologies are then contrasted with the international context in order to provide solid insights to evaluators and program managing authorities facing ex ante impact assessment. Research design: All European RDPs from the period 2007 through 2013 (a total of 88) and their corresponding available ex ante evaluations (a total of 70) were analyzed focusing on the socioeconomic impact assessment. Results: Only 46.6% of the regions provide quantified impact estimations on socioeconomic impacts in spite of it being a compulsory task demanded by the European Commission (EC). Recommended methods by the EC are mostly used, but there is a lack of mixed method approaches since qualitative methods are used in substitution of quantitative ones. Two main difficulties argued were the complexity of program impacts and the lack of needed program information. Conclusions: Qualitative approaches on their own have been found as not suitable for ex ante impact assessment, while quantitative approaches—such as microsimulation models—provide a good approximation to actual impacts. However, time and budgetary constraints make that quantitative and mixed methods should be mainly applied on the most relevant impacts for the program success.