In 1990, Michael Porter's The Competitive Advantage of Nations was published. Porter had already established his name with two books on industry analysis and company strategy that had become instant classics in their field. Twenty-five years later The Competitive Advantage of Nations has undoubtedly become a classic. The purpose of this special edition of the Competitiveness Review is to contribute to the discussion of what lessons the book and the work it triggered holds today. There is no doubt that the questions Porter raised 25 years ago remain critical today; maybe even more so than ever.The collection of papers in this special issue pulls together the learnings from applying Porter's competitiveness framework to a range of conceptual issues and specific locations. It cannot hope to provide a comprehensive discussion of the contribution that The Competitive Advantage of Nations has made; that is beyond the scope of this special issue. But it aspires to indicate where specific lessons can be drawn or a direction for future research can be set.