Location: What about Hudson Yards? The city and the M.T.A. are preparing bids for the eastern and western yards at the same time. What sort of thing will be built there?

Mr. Doctoroff: It’ll be a mixed-use development between two platforms, two railyards; you’ll be looking between 12 and 14 million square feet. It’ll be some mix of residential and commercial and retail, potentially with a hotel. There will be significant connections with the waterfront. There will be at least one cultural institution. Our hope is that we produce something that is maybe New York’s 21st-century Rockefeller Center.

Location: Is that too big a job for one developer?

Mr. Doctoroff: Doesn’t have to be one-it can be someone bidding on the eastern rails, someone bidding on the western rails. There are partnerships that bid each of the railyards. The one thing that makes this a little bit different is that the platform itself has to be specifically suited to the development above it.