In this report, the authors provide the U.S. Department of Homeland Security's (DHS's) Office for Civil Rights and Civil Liberties with analysis of the Department's use of terminology in referring to people in certain racial, ethnic, national, and religious groups. The authors also identify ways to improve departmental documentation, processes, and procedures and create an organizational culture that supports the lasting implementation of updated terminology. This comprehensive analytic document (1) contains guidance that would enable DHS to update terminology that aligns with the proposed 2021 U.S. Citizenship Act and (2) identifies ways for DHS to foster an organizational culture that supports the ongoing use of the updated terminology in three principal categories: immigration, public order policing, and terrorism/counterterrorism. This report will inform DHS efforts to develop a departmental lexicon consistent with current Executive Orders, the objectives of the U.S. Citizenship Act, and recently issued departmental policies regarding the use of certain terminology.