Paul Simon once said that a songwriter's supreme challenge was being complex and simple at the same time-writing songs with lasting depth that are also simple enough to be memorable. Jimmy Van Heusen was a master at this kind of song. His music was complex, with deeply rich chord changes any jazzman can embrace, but also possessed catchy, crystalline melodies of exceeding sing-ability. His songs were meant to be sung, not just listened to, and they were sung by the best, with Frank Sinatra and Bing Crosby at the top of that list.