As both older and newer immigrant gateway metropolitan areas grow more racially diverse, scholars of neighborhood change want to know whether these areas are also becoming more residentially integrated. While it is logically and mathematically plausible to assume that increasing racial diversity directly leads to increased racial residential integration, this paper argues that the empirical reality may actually be the opposite. To investigate this concept, we use statistical and cartographic methods to analyze tract-level Census data of the Washington, D.C. metropolitan area, a case study that is both representative and unique. Results indicate that increasing racial diversity in the Washington, D.C. metropolitan area between 1990 and 2010 coincided with increased racial residential segregation. We discuss the theoretical and methodological implications of these findings and make recommendations for future research.