I use a rich new dataset of Louisiana slave records to answer long-standing questions about manumission. I examine who was manumitted, by whom, and whether manumittees paid prices above market for their freedom, shedding some light on the debate of the efficiency of slavery. Legal changes after the Louisiana Purchase allow us to conclude that manumission laws were quite important in determining the terms at which manumission agreements were struck: when slaves lost the right to sue for self-purchase at market price, there was a precipitous drop in the number of manumissions, while prices paid increased.