"The 1964 Civil Rights Act is best known as a monumental achievement of the civil rights movement, but it also revolutionized the lives of American women. Title VII of the law made it illegal to discriminate "because of sex." But Congress gave little guidance about how much it wanted to change in a "Mad Men" world where women played mainly supporting roles. It was up to the Supreme Court, then, to endow that simple phrase with meaning, and its decisions set off seismic changes in how the nation sees working women - women like Ida Phillips, denied an assembly line job because she had small children and was assumed to be unreliable; or Kim Rawlinson, who fought to be an Alabama prison guard because she believed that being 5'3" and 115 pounds didn't mean she couldn't do a "man's job"; or Mechelle Vinson, whose years of sexual abuse by her boss showed that sexual harassment is just as much a denial of equal opportunity as a lower paycheck; or Ann Hopkins, voted down for partnership at Price Waterhouse because the men in charge thought she needed "a course at charm school." But if there is much to celebrate in America today, where women are Supreme Court justices and presidential contenders, there is also a long way to go. Peggy Young, whose case was heard by the Supreme Court in December 2014, was forced onto unpaid leave while pregnant because UPS refused to accommodate a temporary lifting restriction imposed by her doctor. To understand this and other remaining obstacles to women's full equality on the job - from "mommy tracking" to unequal pay to a sex-segregated workforce - we need to know how we got here. Because Of Sex tells that story, and gives an unsung group of heroines their due"--