This collection of cross-cultural essays on reproduction and childbirth extends the work of Brigitte Jordan, who helped generate and define the field of the anthropology of birth. The authors' focus on authoritative knowledge - the knowledge that counts, on the basis of which decisions are made and actions taken - highlights the vast differences between birthing systems that give authority of knowing to women and their communities and those that invest it in experts and machines. The text presents first-hand ethnographic research conducted by anthropologists in 16 different societies and cultures and includes interdisciplinary perspectives of a social psychologist, a sociologist, an epidemiologist, a staff member of the World Health Organization, and a community midwife.