As the leading voice of conservative pragmatism on the Supreme Court, Justice Sandra Day O'Connor has surprised both liberals and conservatives by crafting new approaches to several areas of American constitutional law. Much of the prior work examining Justice O'Connor’s Supreme Court record has tried in vain to demonstrate that she stakes out legal positions based on her gender. In this comprehensive and systematic study, Robert W. Van Sickel explores the full corpus of O'Connor’s opinions, as well as her various speeches, articles, and work on the Arizona Court of Appeals. He identifies a set of flexible yet consistent values that pervade her decisions during the past fifteen years.