This report aims to diagnose what drives corrupt behaviour in Nigeria, and the types of beliefs that support practices understood to be corrupt. Its findings are based largely on a national household survey jointly developed by the Chatham House Africa Programme and the University of Pennsylvania’s Social Norms Group (PennSONG), in collaboration with Nigeria’s National Bureau of Statistics as well as a network of academics and practitioners from Nigerian universities and NGOs. The findings present new evidence of the social beliefs and expectations that influence some day-today forms of corruption in Nigeria. Fuller details of the survey and associated research are given in the body of the report, as well as in the annex to the main text.