This book walks new and experienced researchers through the use of comparative judgement methods, drawing on examples and case studies from the fields of education, political geography, linguistics and others. Assuming no prior knowledge of qualitative methods, it includes step-by-step practical guidance on designing studies, selecting and using platforms and software, and collecting and analysing data. It also discusses the more complex questions of validating, interpreting and reporting outcomes. Gaining popularity across the social sciences for its value in tackling difficult measurement problems, comparative judgement centres around the comparison of pairs of objects. Its robust results draw on human beings’ remarkable consistency when comparing one thing to another, and this simple but powerful underpinning means that it can be used to address research questions across disciplines that evade other approaches.