On May 10, 2018, USCIS issued a Policy Memorandum entitled “Accrual of Unlawful Presence and f, J, and M Nonimmigrants,” providing new guidance to USCIS officers in the calculation of unlawful presence of students, vocational students, and exchange visitors who remain in the US beyond their authorized period of stay. The Memo is a departure from policy guidance put in place more than 20 years ago. To make sense of the new policy, Forbes turned to Mayer Brown’s Paul Virtue, who, in 1997, authored the “Virtue Memo” when he served as Executive Associate Commissioner for Programs of the Immigration and Naturalization Service (INS). The Virtue Memo established the government’s interpretation of unlawful presence which has been adopted and applied ever since. The new Memo reinterprets how USCIS officials should calculate unlawful presence for F-1, J-1, and M visa holders, as well as their dependent family members.