The relationship between Sandra Day O'Connor and Ruth Bader Ginsburg—Republican and Democrat, Christian and Jew, western rancher's daughter and Brooklyn girl—transcended their differences. Strengthened by each other's presence, these groundbreaking judges, the first and second to serve on the highest court in the land, have transformed the Constitution and America itself, making it a more equal place for all women. Filed with intriguing anecdotes, Linda Hirshman's dual biography reveals how these trailblazers fought for their own recognition in a male-dominated profession—battles that would ultimately benefit every American woman.