The Lefcourt Colonial Building is a 47-story office building located on Madison Avenue with 41st Street in Midtown Manhattan, in New York City. The 164-metre-tall (538 feet) neo-Gothic building was completed in 1930.

The project consisted in the repositioning of the historic office building into a highly desirable Class-A property.
The focus was to optimize the building’s layout by relocating access points, creating a larger continues and more attractive retail space with new floor-to-ceiling façade elements and introducing a grand new lobby. The improvement programme also included a full restoration of the Art Deco-era ornate facade and the redesign of several office floors.

Gregory Martínez de Riquelme was the lead architect for this project during his tenure at Gensler New York.