Summers' work on Bruce Forsyth's Hot Streak garnered the attention from Nickelodeon, which hired him as the host of Double Dare from 1986–1993.

[4] Double Dare's popularity led Summers to other hosting jobs including the syndicated Couch Potatoes in 1989, and Nickelodeon's What Would You Do?

Summers also had a rare dramatic performance in the Nickelodeon-produced Halloween program Mystery Magical Special, which also highlighted his skills as a stage magician.

Summers also made celebrity guest rounds on other game shows including Scrabble, Super Password, Talk About, Lingo, To Tell the Truth, Win, Lose or Draw, and Hollywood Squares.

After Double Dare's cancellation in 1993, Summers co-hosted Our Home, a daily talk show aimed at homemakers, on Lifetime.

In late 2006, Sony Pictures Television and KingWorld planned a new game show called Combination Lock, with Summers hosting the first pilot.

Summers was a young page at CBS when The Price Is Right premiered with The Joker's Wild and Gambit in 1972, and he often asked advice of Barker, Jack Barry and Wink Martindale—the shows' respective hosts—about a hosting career.

He claims it was the best possible education and training in the game show field, and it was during this time that Summers got his first on-air experience, as a fill-in announcer on The Joker's Wild.

He has also played himself on The Cleveland Show, Robot Chicken, Workaholics, and Sanjay & Craig, and appeared in special segments on ABC's The Chew.

He is the subject and executive producer of On Your Marc, a documentary that chronicles his life and development of his one-man theater show, featuring interviews with Neil Patrick Harris, Ryan Seacrest, Guy Fieri and Seth Green, and was directed by Mathew Klickstein.

[8] He hosted a number of early preview screenings and live events as part of a nationwide promotional tour of the film in October 2017.

[15] His one-man show The Life and Slimes of Marc Summers played off-Broadway at New World Stages from February to June 2024.

In 1999, Summers produced a VHS video box set with Hollander about his experience, called Everything in Its Place: My Trials and Triumphs with Obsessive Compulsive Disorder.

Going public with his OCD cost Summers a job as host of a Hollywood Squares revival, and he was replaced by Tom Bergeron.

[20] In a 2015 interview on the Philadelphia-based Preston & Steve radio show on WMMR, Summers revealed that six years before, in 2009, he had "stomach problems" and had been in a lot of pain.

The initial doctor recommended chemotherapy, but fearing the pain and illness involved, Summers sought the opinion of another oncologist in Chicago.

[21] On April 10, 2018, Summers was again a guest on Preston & Steve, and discussed flying to the University of Pennsylvania Medical Center from his home in Santa Barbara for further treatment.