Protecting NATO Secret and Foreign Government Information

Overview guidance for U.S. contractors on handling Foreign Government Information (FGI) and NATO information: describes FGI under CNSI and re-marking to U.S. equivalents; outlines NATO classification levels (NU, NR, NC, NS, CTS, ATOMAL); and emphasizes applying the same controls as equivalent U.S. classifications (e.g., CUI/Secret) with least privilege, robust logging, and approved systems. It clarifies marking/segregation requirements (NATO vs. non-NATO, ATOMAL), considerations for labeling external media, and that dedicated isolation is generally unnecessary when appropriate access controls are in place, referencing relevant DoD directives and 32 CFR 2001.54.