The Durst Organization has signed Cushman & Wakefield, the world's largest, privately held commercial real estate services firm, to a ten-year, 10,222 s/f lease on the 45th floor of One World Trade Center, 285 Fulton St. The space will serve as the company's Downtown headquarters. Cushman & Wakefield - whose world headquarters is situated in Manhattan at 1290 Ave. of the Americas - assumed occupancy on September 1. The Durst Organization was represented on the transaction by Eric Engelhardt, the company's vice president and director of leasing at One WTC. Lo Russo represented Cushman & Wakefield.