Illinois Secretary of State Jesse White says some of his offices in downtown Chicago will be closed because of the NATO summit this weekend.
Two secretary of state locations in Chicago's business Loop will be closed Friday and Monday. More than 50 heads of state will be coming to Chicago for the summit.
City officials say there'll be street closures and traffic is expected to be bad on Monday morning as the leaders head back to O'Hare International Airport.
Spokesman Dave Druker said closing the offices might help ease vehicle congestion and keep people who want to take care of driver and vehicle services from getting stuck in traffic.
Customers are encouraged to visit facilities in other parts of the city, which will remain open.