(written from a Production point of view)
Michael Steven DiMente is an actor, singer, and songwriter who appeared as a Deltan ambassador in Star Trek IV: The Voyage Home. He received no credit for this appearance. His costume was later sold off on the It's A Wrap! sale and auction on eBay. 
DiMente started his acting career as a child actor in the 1960s. He has made appearances in many films, commercials and television series with his first big part in the television western Evil Roy Slade (1972, with Henry Gibson, Arthur Batanides, Larry Hankin, and Ed Begley, Jr.). Other appearances in film as a background actor include the crime drama The Godfather: Part II (1974, with Marianna Hill), the action drama Earthquake (1974, with Geneviève Bujold, John S. Ragin, George Murdock, Gene Dynarski, and Jerry Hardin), the comedy Cheech and Chong's Next Movie (1980, with Evelyn Guerrero, Faith Minton, John Paragon, and Rick Sawaya), the comedy Stripes (1981, with John Larroquette, Lance LeGault, and William Lucking), the musical Grease 2 (1982, with Pamela Adlon, Christopher McDonald, Richard Epper, Freddie Hice, and Tom Villard), the drama The Karate Kid (1984, with Larry Drake), the science fiction film Back to the Future (1985, with Christopher Lloyd, Ivy Bethune, Jeff O'Haco, and Sachi Parker), and the sequel The Karate Kid, Part II (1986, with George O'Hanlon, Jr.).
He also worked as background actor and stand-in on television series such as Adam 12, Baretta, Barnaby Jones, Cheers (with Kirstie Alley, Kelsey Grammer, and Bebe Neuwirth), Charlie's Angels, CHiPs (with Michael Dorn and Robert Pine), Dallas, Dynasty (with Joan Collins), Family Ties (with Brian Bonsall), Fame, Fantasy Island (with Ricardo Montalban), Hart To Hart, Highway To Heaven, Hill Street Blues, I Dream Of Jeanie, Kung Fu, Little House On The Prairie, MacGyver, M*A*S*H, Murder She Wrote, St. Elsewhere, Starsky and Hutch (with David Soul), T.J. Hooker (with William Shatner, James Darren, and Richard Herd), The Bionic Woman, The Brian Keith Show, The Dukes Of Hazard, The Love Boat, The Mary Tyler Moore Show, The Streets Of San Francisco, The Six Million Dollar Man, and Who's The Boss?.