[1] Horst came from U.S. Embassy Berlin, where she was Minister Counselor for Public Diplomacy for Mission Germany and a member of the Senior Foreign Service.

Previously, Elizabeth served as SCA’s Director of the Security, Transnational Affairs and Assistance (STA) Office.

She led the interagency task forces of the United States' embassy in Ukraine during the annexation of Crimea by Russia and the 2014 Ukrainian revolution.

[1][2] On July 29, 2018, she replaced James D. Melville Jr. as the United States' Chargé d'affaires ad interim to Estonia.

[3][4] In February 2024, U.S. President Joe Biden nominated Horst to serve as ambassador to Sri Lanka.