Rohini Somanathan's interests lie at the intersection of Development Economics, Public Economics and Political Economy. A major strand in her research explores mechanisms through which public institutions and community behavior influence patterns of mobility and group inequality. This includes work on the politics of caste identities in India and racial segregation in the United States. Current projects include research on rural credit markets and microfinance institutions, wage and productivity effects of economic liberalization in India and on distribution and environmental change.

She was a Research Fellow from 2011 until 2015.