Boyd Patterson, who heads up the city's Gang Task Force, said a pact has been worked out for cooperation in gang initiatives across the border.
Walker County, Ga., will be working closely with Hamilton County authorities on the gang problem.
A signing ceremony is set for Thursday afternoon at the Gang Task Force office across from City Hall.
Walker County Sheriff Steve Wilson will take part along with Chattanooga Mayor Ron Littlefield, Hamilton County Mayor Jim Coppinger, Hamilton County Sheriff Jim Hammond and Mr. Patterson.
Officials said, "This agreement allows law enforcement officers in both counties to work more efficiently and effectively in the investigation of gang cases that cross jurisdictional boundaries."