On April 11, 2025, a significant change to US immigration enforcement took effect. The United States Department of Homeland Security (“DHS”), through US Citizenship and Immigration Services (“USCIS”), began implementing a new registration requirement for certain foreign nationals physically present in the United States for 30 days or longer. This change stems from President Trump’s January 2025 Executive Order titled Protecting the American People Against Invasion and is detailed in an Interim Final Rule published in the Federal Register on March 12, 2025. This post explains what the new registration requirement entails, who it affects, and what actions foreign nationals must take to remain in compliance with US immigration law.