Federal Communications Commission | BBC World Service | National Park Service | Internal Revenue Service | Distinguished Service Order | Special Air Service | United Parcel Service | Meritorious Service Medal (United States) | United States Postal Service | National Health Service | Meritorious Service Medal | Metropolitan Police Service | United States Forest Service | German Academic Exchange Service | Clear Channel Communications | Secret Intelligence Service | Immigration and Naturalization Service | Distinguished Service Cross | National Defense Service Medal | National Service | United States Secret Service | Royal Naval Air Service | National Weather Service | Agricultural Research Service | Special Broadcasting Service | Distinguished Service Cross (United States) | On Her Majesty's Secret Service (film) | On Her Majesty's Secret Service | Internet service provider | United States Foreign Service |
Within the United States and Canada, Neustar administrates the North American Numbering Plan, the authoritative directories that manage virtually all telephone area codes and numbers, and enables the routing of calls among thousands of competing communications service providers (CSPs).