The Legacy at Millennium Park is a conventionally reinforced concrete frame with an aluminum and glass curtain wall exterior skin. It is a 72-story mixed-use building that combines retail, academic, and residential spaces and 454 parking spaces. A 13-story podium houses retail uses on the first floor, an expansion of the School of the Art Institute on the second and third floors, parking on floors four through 12, and an athletic facility on the 13th floor (including a pool, squash courts, activity rooms, etc.).

The site included three buildings contributing to the Loop Retail National Register Historic District and the City of Chicago Jewelers Row District. Their façades were preserved to maintain the historical integrity of the site. The remainder of the structures was demolished.