Other major employers, such such as AT&T Inc., have transferred hundreds of jobs from the suburbs to the city. Walgreen has focused on the Old Main Post Office, the hulking structure that straddles the Congress Parkway feeder ramp to the Eisenhower Expressway, people familiar with the company's search said. Related: • Meet the dealmaker who has Walgreen's HQ buzzing • Is Wasson losing control of Walgreen?