Renovating the World: The U.N. Under Construction

The Secretariat's Exterior
One of the top priorities of the five-year, $1.9 billion renovation project is to make the U.N., which officially opened in 1951 and has never been renovated, green. "This is sort of a total house cleaning," Adlerstein said. On the outside, the exterior glass-wall facade will be removed a floor at a time and replaced with new glass that will reduce the complex's energy consumption.

• Portraits from the U.N. General Assembly