Arkansas Best Corporation is a holding company through its subsidiaries is engaged primarily in motor carrier freight transportation. The Company�s principal operations are conducted through its Freight Transportation operating segment, which consists of ABF Freight System, Inc. and other subsidiaries of the Company that are engaged in freight transportation. ABF provides interstate and intrastate direct service to more than 44,000 communities through 275 service centers in all 50 states, Canada and Puerto Rico. Through arrangements with trucking companies in Mexico, ABF provides motor carrier services to customers in that country as well. As of December 31, 2011, ABF operated approximately 3,800 tractors and 20,100 trailers in its linehaul and local pickup and delivery operations. In June 2012, the Company acquired Panther Expedited Services, Inc. from Fenway Partners LLC.