This edited volume analyzes mistakes in different areas of international relations including the realms of security, foreign policy, finance, health, development, environmental policy and migration. By starting out from a broad concept of mistakes as “something [considered to have] gone wrong” the edited volume enables comparisons of various kinds of mistakes from a range of analytical perspectives, including objectivist and interpretivist approaches, in order to draw out answers to the following guiding questions: • How are actors made responsible?