PAPER ABSTRACT: Between 2006 and 2010, nearly 150 women were unlawfully sterilized in California prisons.  Prison medical staff have defended the procedures as a service to taxpayers, and even to the women themselves, as a way of preventing the birth of “unwanted children.”   This chapter situates the recent sterilization of women in California prisons in relation to the history of eugenics in the United States as well as broader patterns of racism, class oppression, reproductive injustice, and mass incarceration.  The central claim is that the current U.S. prison system is not just implicated in eugenics at particular moments, but in its very structure, insofar as it systematically prevents certain groups of people – primarily poor people and people of color, who are targeted for disproportionate police surveillance, arrest, and incarceration – from making basic decisions concerning their own reproductive capacity.  The reproductive justice movement led by women of color activists and scholars provides a framework for dismantling the eugenic structure of mass incarceration, beyond the alternatives of pro-choice and pro-life.