In this chapter, we will take a look at what we know about pay equity in academia from previous studies. As will be seen, most of the attention in the empirical literature on pay equity has examined whether male and female faculty in tenure-eligible positions with similar work-related characteristics are on average paid the same. This narrow focus is driven largely by data limitations. I first review what we know from descriptive statistics on the average pay for men and women in academia. The next section provides information on what we know about pay equity for tenure-eligible faculty from published studies. Many of these studies used nationally representative data on individual faculty in the United States and thus their results do not indicate whether there is pay inequity at any single institution. Finally, the chapter concludes with a review of what we know about pay equity for staff.