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.