Phillips was a Starfleet officer who lived during the mid-23rd century. He served in the sciences division aboard the USS Enterprise under Captain James T. Kirk, during the 2260s, as one of the ship's astrobiologists.
In 2268, Phillips was recommended to be among the landing party by both the M-5 multitronic unit and Captain Kirk, to planet Alpha Carinae II. M-5's reason for selecting the officer was that Phillips had previously surveyed 29 biologically similar class M planets. (TOS: "The Ultimate Computer")