Non-knowledge should not be simply regarded as the opposite of knowledge, but as complementary to it: each derives its character and meaning from the other and from their interaction. Knowledge does not colonize the space of ignorance in the progressive march of science; rather, knowledge and ignorance are mutually shaped in social and political domains of partial, shifting, and temporal relationships. This volume’s ethnographic analyses provide a theoretical frame through which to consider the production and reproduction of ignorance, non-knowledge, and secrecy, as well as the wider implications these ideas have for anthropology and related disciplines in the social sciences and humanities.