This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book focuses on a collective of international scholars who are researching at the intersections of media, mobility and sociality. It explores the divergent vantage points of the interplay between mobilities and socialities, analysing material conditions, situated contexts and the ascribed meanings to people’s movements, their media practices and social relations. The book argues that mobile socialities is not only concerned with connections across media, mobility and sociality, but also with the contrary reality of material and imaginary worlds. It explores how the concept is used to question earlier works, and addresses a core theme of the individual and their digital networks in previous research. The book addresses the question of breathing - both metaphorically as well as in real terms: without lungs that move, nothing else counts.