Published in International Perspectives in Sexual and Reproductive Health, March 2009, by Anuja Jayaraman, independent consultant; and Vinod Mishra and Fred Arnold of ICF Macro. Countries in South Asia demonstrate a strong cultural preference for sons, which may influence fertility desires and contraceptive use. Analyzing data from nationally representative surveys in Nepal, India, and Bangladesh, this study shows that son preference remains widespread in all three countries and has a major influence on reproductive behavior. Policies and programs need to include mechanisms to make daughters more valuable to families and to remove gender differences within households through family planning, education, and social programs.