* Tommy Dorsey: Dorsey was a bandleader and trombonist who led one of the most popular big bands of the 1940s. Sinatra sang with Dorsey's band for several years and learned a great deal from him about musicianship and showmanship.
* Nat King Cole: Cole was a jazz pianist and singer who was one of the most popular entertainers of the 1950s. Sinatra admired Cole's rich, velvety voice and his ability to interpret a song.
* Frank Loesser: Loesser was a songwriter who wrote some of the most famous songs that Sinatra ever recorded, including "Luck Be a Lady," "My Kind of Town," and "I've Got You Under My Skin."
* Nelson Riddle: Riddle was an arranger and conductor who worked with Sinatra on many of his most famous recordings. Riddle's lush, romantic arrangements helped to create Sinatra's signature sound.