My work focuses on between population rates and social practice. How are individual actions coordinated into stable population rates? Do population rates have causes? What roles do individual intentions and strategies play in the formation of rates? What is the social structure of intentions? is this structure transformed by the experience of pervasive uncertainty? I approach these theoretical questions using a combination of ethnographic and demographic methods. The empirical object of my work is kinship, and particularly reproduction: childbearing, contraceptive use, abortion, infertility, and infant mortality. I have written two books: Uncertain Honor: Modern Motherhood in an African Crisis (2006) and (with Morgan, Bachrach, and Kohler) Explaining Family Change and Variation (2011). I am currently working on a book tentatively titled Sex in Public: Population and the paradox of choice.