The introduction establishes the framework and examines themes of entanglement, encounters and exchanges – and the complex intersections between them – that lie at the heart of this volume. Arguing that the war can be understood as a turning point in the history of encounters, it explores their specific contexts – from camps and hospitals to London clubs and besieged cities to musical and textual encounters. What kinds of entangled pre-war histories informed such encounters which then shape a range of issues, from cross-racial intimacy and identity formation to anti-colonial movements, civil rights movement and visions of a post-war world? The reader is introduced to the traces and textures of these encounters, their global reach and range, from the contingent and interpersonal to cultural and political strategies of propaganda and revolution. The introduction reflects, too, on the concepts and methodology, making the case for ‘encounter’ as a capacious and flexible term which allows us to showcase the fraught contours, highlight ambiguous zones and admit messy, difficult, even painful histories. The three parts of the book are delineated – Spaces, Process and Instrumentality – and how the diverse case studies come together to suggest the rich possibilities of this approach in its multiple iterations and locations.