Insects display a staggering diversity of mating and social behaviours. Studying these systems provides insights into a wide range of evolutionary and behavioural questions, such as the evolution of sex, sexual selection, sexual conflict, and parental care. This edited volume provides an authoritative update of the landmark book in the field, The Evolution of Insect Mating Systems (Thornhill and Alcock, 1983), which had such a huge impact in shaping adaptationist approaches to the study of animal behaviour and influencing the study of the evolution of reproductive behaviour far beyond the taxonomic remit of insects. This accessible new volume brings the empirical and conceptual scope of the original book fully up to date, incorporating the wealth of new knowledge and research of the last 30 years. It explores the evolution of complex forms of sex determination in insects, and the role of sexual selection in shaping the evolution of mating systems. Selection arising via male contest competition and female choice (both before and after copulation) are discussed, as are the roles of parasites and pathogens in mediating the strength of sexual selection, and the role that parental care plays in successful reproduction. The Evolution of Insect Mating Systems is suitable for both graduate students and researchers interested in insect mating systems or behaviour from an evolutionary, genetical, physiological, or ecological perspective. Due to its interdisciplinary and concept-driven approach, it will also be of relevance and use to a broad audience of evolutionary biologists.