Clifford Chance is embarking on the biggest logistical exercise in its history with its move of 2,570 staff from Aldersgate Street to Canary Wharf. Last weekend 650 staff - mostly non-fee-earners, plus the real estate and tax group - moved over to the Docklands. They will be followed this weekend by the finance and capital markets teams and then by corporate and litigation. London managing partner Peter Charlton said: "It's been about the smoothest-run project we've ever done, and we've had tremendous help from Canary Wharf." The custom-built tower in Canary Wharf is a million square feet and is understood to be costing £40 per square foot. Because Clifford Chance has been unable to fill the entire space as originally configured, it has let 100,000 square feet back to Canary Wharf. Charlton said: "It means we're not looking for a sub-tenant." Clifford Chance's exit from the City means that its 438,000 square feet of space in its Aldersgate offices will become vacant. Canary Wharf is taking over the lease of the old building.