(written from a Production point of view)
Patrick J. Cronin (born 1941) is the actor who played the role of Erko in the Star Trek: The Next Generation fifth season episode "Cost of Living". Cronin filmed his scenes for this episode on Wednesday 5 February 1992, Thursday 6 February 1992, and Monday 10 February 1992 on Paramount Stage 8 and 9.
Cronin co-starred with fellow TNG guest actor Paul Sorvino on the short-lived police drama The Oldest Rookie. He previously had a recurring role on the television sitcom Alice during the 1978-79 season. Starring in this series was Star Trek: The Original Series guest actor Vic Tayback. Cronin also made several appearances as George "Sparky" Henderson in the more recent sitcom, Home Improvement (1996-1999).
Aside from his appearance on TNG, other TV shows on which he has made guest appearances include Fantasy Island (starring Ricardo Montalban), Archie Bunker's Place (with Bill Quinn), Cheers (with Kelsey Grammer, the first two episodes of L.A. Law (with Corbin Bernsen, Night Court (with John Larroquette), The Wonder Years (with Robert Picardo), and Seinfeld (with Jason Alexander).
He has also appeared in a few made-for-TV movies, including 1980's Brave New World (featuring Casey Biggs, Jeannetta Arnette, and Julie Cobb), 1984's The Cartier Affair (starring Joan Collins, Ed Lauter, and Charles Napier), 1988's Shakedown on the Sunset Strip (with David Graf), 1990's A Family for Joe (with Barbara Babcock and Janet MacLachlan), and 1991's Lucy & Desi: Before the Laughter (with Alan Oppenheimer). The latter movie was a biography on Lucille Ball and her husband, Desi Arnaz, who were the founders of Desilu Studios, the production company that first produced the original Star Trek.
Cronin's feature film credits include 1984's Splash (featuring Clint Howard, Bill Smitrovich, Valerie Wildman, Christopher Thomas, and Charles Macauley), 1990's Sibling Rivalry (starring Kirstie Alley and Scott Bakula), and 1992's Dr. Giggles (starring Larry Drake, Cliff DeYoung, John Vickery, and William Dennis Hunt and co-written and directed by Manny Coto).
Among his most recent credits are episodes of The Magnificent Seven (2000, with Brad Greenquist, Andrew Kavovit, Ron Perlman, Michelle Phillips, and Rick Worthy) and Sabrine, the Teenage Witch (2001, with Mark Chaet) and the 2004 comedy Forever for Now.
Cronin is currently Director of the division of Performing Arts in the Honors College at East Tennessee State University.