The funds committed to cohesion policy are the second highest category of expenditure in the European Union budget and this policy is among the most evaluated. There are different tools and methodologies to carry out the evaluation each of them with their own merits and also their flaws and biases. This special issue explores the three main types of approaches, theory-based evaluation, counterfactual (econometrics) and macroeconomic models, to assess cohesion policy by presenting a set of contributions within these methodologies. The first set of contributions focus on the assessment of cohesion policy by means of macro models putting a special emphasis on the European Commission newly developed model RHOMOLO. The second set of contributions is linked to the econometric evaluations of different aspects of cohesion policy and finally a theory-based evaluation exercise closes this special issue.