The original building was 11 stories with 554 guest rooms. Lapidus employed a curved facade design, oriented southeast to capture trade winds. The arched openings on the facade were called "Swiss cheese holes," becoming its signature element.
The lobby spans 17,000 square feet. The "Staircase to Nowhere" is Lapidus's most famous design, actually leading to a coat check and ladies' lounge with limited functionality, designed to allow guests to make a dramatic entrance in full view of the lobby. The flower beds beneath the staircase are original elements preserved since the 1954 opening.
Lapidus's bow tie motif runs throughout the entire hotel, from floor mosaics to pool shapes.
In 2002, architect John Nichols led the expansion, adding the 36-story Trésor Tower and 18-story Sorrento Tower. The 2008 renovation preserved Lapidus's design language. The lobby now features three inverted wedding cake crystal chandeliers designed by artist Ai Weiwei, costing $1 million.
In 2007, it received the American Institute of Architects' "America's Favorite Architecture" designation. On December 22, 2008, it was listed on the National Register of Historic Places. In 2012, the Florida AIA ranked it first in "Florida Architecture: 100 Years. 100 Places."