Contracting Officer's Technical Representative

A Contracting Officer's Technical Representative (COTR) is a business communications liaison between the United States government and a private contractor. The COTR is normally a federal or state employee who is responsible for recommending actions and expenditures for both standard delivery orders and task orders, and those that fall outside of the normal business practices of its supporting contractors and sub-contractors.

Source: Wikipedia — Contracting Officer's Technical Representative (CC BY-SA 4.0)