Westervliet sent orders removing Enterprise from responsibility for the asteroid spaceship Yonada in 2268 after James Kirk initially proved unable to divert its course from inhabited Daran V system. (TOS: "For the World is Hollow and I Have Touched the Sky")
Westervliet was played by Byron Morrow, who previously appeared as another admiral, James Komack, in "Amok Time". Westervliet's name was only given in the episode's end credits. The name was previously referenced in the script for "Amok Time", Admiral Komack was almost entirely referred to as Westervliet in the script for "Amok Time". According to the de Forest Research review of the 29 May 1967 draft of the script for "Amok Time", the following was noted of the proposed name "Admiral Westervliet": "There is a serving Captain in the United States Navy, Westervelt. To avoid conflicts, suggest: Komack, used in previous scripts."