This book, entitled "Learning in innovation policies: the case of the Porter report and cluster policy in Portugal", focuses on the dynamics and evolution of innovation policies in the Portuguese context, with particular emphasis on the proposals put forward by Michael Porter's report.Using a methodology that combines in-depth interviews with experts and analysis of secondary documentation, this study seeks to uncover the mechanisms underlying the different "filters" in the process of learning public policies. These filters, it turns out, have played a crucial role in shaping and influencing public policies associated with clusters in Portugal.The work is also dedicated to tracing a detailed timeline, allowing us to understand the evolution and adaptation of cluster policy from its conception, inspired by the ideas of the Porter report, to its most recent manifestations and implementations on the national scene.The results obtained in this research are revealing, highlighting notonly the trajectory and metamorphosis of innovation policies in Portugal, but also the role of the Porter report and the idea of "clusters".