Carmen Twillie is a vocalist who, aside from singing the lead in "Circle of Life," also provided a voice for at least one track in The Power of One.
Kevin Lightner is Zimmer's technical chief.
Pete Haycock, a talented electric guitarist, performed on Zimmer's K2 score as well as on the track "Thunderbird" on Thelma and Louise.
Jay Rifkin has co-produced many of Zimmer's scores, and he helped to write and arrange many of the non-Zimmer pieces on Rhythm of the Pride Lands as well as the tracks on that CD deriving from "Under the Stars" ("Lala" and "Busa") on the TLK soundtrack, which is itself another track designated as having been co-arranged by him.
Mark Mancina appears on the TLK soundtrack as being the arranger and producer for most of the songs, excluding the ones Zimmer arranged himself ("Circle of Life" and "Be Prepared"); his connection directly with a Zimmer soundtrack is with Millennium: Tribal Wisdom and the Modern World, on which he is listed as having (with another) arranged and performed the compositions on that CD.