Henry J. Waternoose III, also known as Mr. Waternoose or simply Waternoose, is the hidden secondary antagonist of Monsters, Inc. He is the founder and former chairman of the company, Sulley and Mike's former boss, best friend, mentor, and father figure, and one of Randall's former henchmen.
- Mr. Waternoose is often thought to be the first film's main antagonist and Randall's boss. This isn't true as the film states itself that Randall is the mastermind.
- He is the last character to be voiced by James Coburn.
- It is currently unknown what his middle name stands for, although a rumor once said it stood for James; however, there was no source stating this.