Born in Dayton, OH, Jenkins first began acting in high school, performing like most actors starting out, in hometown theater productions. After graduating, Jenkins enrolled at Antioch College where he pursued a degree in the liberal arts. Seeking acting work wherever he could, Jenkins honed his craft by joining a number of regional companies while still in college, thereby gaining valuable practical experience. During this apprenticeship, Jenkins was exposed to the works of such masters as Shakespeare, George Bernard Shaw, Tennessee Williams, and Arthur Miller, whom he credited for shaping the rest of his life.After college, Jenkins moved to Louisville, KY, where he joined a growing community of young playwrights and actors. Home to many of America's best new playwrights (including Beth Henley and Marsha Norman), the city was considered a mecca of rising talent. It was there, in 1964, that Jenkins helped found the prestigious Actor's Theatre of Louisville. In addition to serving as their Associate Artistic Director, Jenkins continued to work with the theater as an actor, director and writer until 1983. In the mid 1980's, Jenkins moved to Los Angeles, where he continued making his living on stage while also undertaking small television roles. One of Jenkins' first on-screen gigs was for a 15-part educational video series for adults called "Adult Math." In it, Jenkins played a math teacher named Frank Hall who instructed viewers how to prepare for their G.E.D. In 1987, Jenkins made his major screen debut in John Sayles' critically acclaimed film, "Matewan" (1987). Though his role was small, the film helped Jenkins make the transition from stage acting to on camera. Starting in the late '80's Jenkins began appearing in a string of guest-starring TV roles. In addition to such shows as "Wiseguy" (CBS, 1987-1990), "Star Trek: The Next Generation" (Synd., 1987-1994), "The X-Files" (Fox, 1993-2002) and "Chicago Hope"(CBS, 1994-2000), Jenkins also portrayed the recurring character of Mike Sloan on the short-lived, but critically acclaimed drama "Homefront" (ABC, 1991-93). In 2001, Jenkins finally landed a regular series of his own. In his most high-profile role to date, Jenkins amused audiences as the bullying profit-minded chief of medicine, Dr. Robert Kelso, on the popular medical dramedy, "Scrubs" (NBC, 2001-08; ABC, 2009-10). An arrogant, obtuse bureaucrat with a penchant for cruelty, the character fit Jenkins like an old glove. Despite his negative qualities, however, Dr. Kelso occasionally showed glimmers of compassion. Even so, the character remained somewhat of a conundrum. As "Scrubs" fans noted, Dr. Kelso was the only principle character who never had an episode told from his point of view.Jenkins most recent feature work included "I Am Sam" (2001) starring Oscar winner Sean Penn, and the 2002 Tom Clancy thriller, "The Sum of All Fears" with Morgan Freeman.