Ambassador Sarek's (Mark Lenard) appearance on Star Trek: The Next Generation would not have worked without Captain Jean-Luc Picard (Patrick Stewart). Aside from a couple of references in its earliest episodes, TNG initially distanced itself from Star Trek: The Original Series. Gene Roddenberry wanted TNG to stand on its own, so he did not allow the show's writers to even mention any characters from TOS. This rule was relaxed over time, as Roddenberry became less involved in TNG's production, eventually leading to guest appearances from a few TOS stars.