The purpose of this chapter is to provide a review of the state of diversity in management literature, including the most recent conceptualizations and measures developed for studying diversity among individuals within organizations. Background on the theoretical and empirical development of surface-level and deep-level diversity is provided. Turning then to separation, variety, and disparity, the chapter will discuss the meaning, form, and assumptions underlying each type of diversity, and offers guidelines for conceptualization, measurement, and theory testing of each. The authors summarize the findings and suggest ideas for future research to move the diversity field forward.