Integrating both ex-ante and ex-post evaluations in the legislative cycle leads to better lawmaking. Legislations can thus produce a fair and optimal impact based on evidence, contributing to solving societal problems in a relevant, efficient, reflexive and fair way. It should be the role of the courts, namely, to verify that this is the case, which they accomplish mainly through the proportionality test. Furthermore, evaluations help the courts to uphold fundamental rights and principles. In practice, however, the quality of regulatory impact assessments has often reported as being flawed and legislators frequently do not take evaluation results seriously. Moreover, the integration of evaluation into the legislative process has enabled the development of innovative types of legislation such as temporary laws subject to review (sunset and experimental legislation), self-regulatory triggering laws (Damocles laws) or legislation by objectives (programmatic laws). In the future, artificial intelligence applied to legislation could possibly reshape the role of evaluation.