Discriminatory social institutions can help to explain why girls leave school prematurely, thereby contributing to persistent gender gaps in both educational and economic participation. The OECD Social Institutions and Gender Index (SIGI) is a composite measure of discriminatory social institutions across non-OECD countries capturing laws, social norms and practices which restrict women’s economic and social role in five areas: 1) discriminatory family codes, 2) restricted physical integrity, 3) son bias, 4) restricted entitlements and resources, 5) restricted civil liberties. This variable often reflects practices such as forcing girls into marriage or their marrying before adulthood due to discriminatory social norms with respect to the status of women in the family and the reproductive role of women.