Melissa Leach, CBE, FBA (born 5 January 1965) is a British geographer and social anthropologist.

She has been the Executive Director of the Cambridge Conservation Initiative since June 2024.

[1] She studies sustainability and development concerns in policy-making and has a focus on the politics of science and technology of Africa.

She was previously the Director of the Institute of Development Studies (2014-2024) located on the University of Sussex campus.

[2] Leach co-founded and directed the ESRC STEPS (Social, Technological and Environmental Pathways to Sustainability) Centre from 2006 to 2014.