The Federation Star for Distinguished Service was a prestigious award that was presented to any Federation citizen who had performed amazing efforts in promoting the Federation and its values.
One such award was rewarded to Lieutenant Commander Clark Terrell in recognition of the essential part he played in trade negotiations on Derus VI, after opening dialogue with the inhabitants, while being stranded on the planet for several years. (ST video game: Starship Creator)
Prior to 2293, James T. Kirk was awarded a star for his long and distinguished service to both Starfleet and the Federation. (TOS - Crucible novel: The Fire and the Rose)