Over the last decade, probably spurred by a resurgence of the phenomenon across the globe, the study of historical piracy has moved away from traditional approaches mostly centred on prosopography and social analysis, and is engaging with active historiographical debates related to the legality of economic activities and the variety of forms of conflict resolution. This has been a most welcome development, as despite the continued appeal of the idea of the pirate in the popular imagination, this figure remains one of the most elusive historical characters to define properly, both in legal and economic terms. This collection, edited by Thomas Heebøll-Holm, Philipp Höhn and Gregor Rohmann, which discusses the changing role of ‘maritime violence’ in the Middle Ages by analysing its legal status and operational reality, is a very good example of these developments. Its focus on the medieval Northern Atlantic, Baltic and Mediterranean seas, which were characterised by dense political and commercial links, and by hotly contested jurisdictional spaces, introduces anglophone readership to recent research on those areas. The volume convincingly argues for the embeddedness of maritime violence ‘into social, legal and economic practices’, and the book as a whole gives a convincing portrait of how the issue was shaped by the ‘constant negotiations and renegotiations of the legality of practices at sea’. This approach allows the contributors to problematise and, in effect, to narrow the semantic area covered by the word ‘pirate’, making clear that the real focus of the contributions is ‘violence at sea’. Collectively, the book’s contributions highlight the existence of a general tendency to mix legal and illegal business in all regions investigated. Conflicts of all sizes are confirmed as providing excellent business opportunities for both individuals and state authorities.