Bob Kelso is the chief of medicine for Sacred Heart Hospital for the first seven seasons of Scrubs (a position held since 1984), though he resigns in the episode "My Dumb Luck".

In the first few seasons, he appears to be a cynical, heartless man who gives mere lip service to patients' well-being, putting more value on the hospital's bottom line and his own personal comfort.

His wife, Enid, and children are never seen on the show, although he frequently comments on his spouse, describing her as morbidly obese, neurotic, and using a wheelchair after an accident that left her paralyzed.

and he has one child by her, a son called Harrison, a gay, drug-dealing heavy metal fan who wrote a scathing musical about him titled Dr. Dad and "shacked up" with the actor playing Kelso.

His father, also a doctor, endeared himself to his poorer patients by accepting gifts such as food and clothing in lieu of actual payment.

[8] Before becoming a doctor, Kelso had a promising career as a shortstop; however, his treatment of other players earned him a permanent ban from the Appalachian League.

[14] One year later, Kelso is still working as a part-time doctor but has now returned to the new Sacred Heart Hospital where he teaches some classes alongside J.D, Turk and Dr. Cox.

He has claimed in the past to be indifferent to the fact that so many people dislike him, but Cox has noted that deep down Kelso does not like to be thought of as the most hated person in the hospital.

[15] In one episode, Kelso reveals that he has always known that his subordinates find ways to treat uninsured people, but pretends not to know to keep the system running and to benefit a friend, Maggie Kent, who has a foot injury.

However, the decision to allow the poor man to die is shown to affect Kelso to the point that he is visibly saddened when he goes home, though he makes sure to hide this fact from the other employees.

[6] Throughout the series, Kelso delights in tormenting Ted Buckland (Sam Lloyd), the hospital's milquetoast attorney, making him do thankless errands and busy work and denigrating him at every chance.

[21] In one episode it is revealed that he is keeping a dorm on the campus as a secret "love nest" because he is unable to bring himself to conduct his affairs in the bed he shared with his wife.

[22] Scholars and other authors studying television have used the character of Bob Kelso to explore medical ethics,[23] as an example of "the antithesis of positivity in the workplace,"[24] and other issues.