"Good-Bye, Radar" is a two-part episode of the television series M*A*S*H that served as the fourth and fifth episodes of the show's eighth season and the 177th and 178th episodes of the series. Part 1 aired on October 8, 1979, with Part 2 airing one week later. The two episodes aired as a one-hour special during off-season reruns on May 12, 1980. As the title of the episode implies, these were the final two episodes to feature Gary Burghoff in his role as Corporal Radar O'Reilly.

These episodes were originally intended to be aired as season seven's finale, but CBS and the producers convinced Burghoff to return for the beginning of season eight. To make up for his imminent departure, Burghoff received a special credit in the show's opening immediately following William Christopher's, which read "also starring Gary Burghoff as Radar". For the first three episodes of season eight, Burghoff’s absence was explained by Radar’s having been sent to Tokyo for some R&R. In two of the three episodes, Burghoff made cameo appearances.

In addition to Burghoff’s departure, these episodes marked the final appearance of Johnny Haymer in his role as Staff Sergeant Zelmo Zale. With the departure of Radar, Hawkeye Pierce, Margaret Houlihan, and Father Mulcahy were the only three characters left on the series who had any connection to the novel and film from which M*A*S*H was derived (with Henry Blake being killed off at the end of season three, Trapper John McIntyre discharged between seasons three and four, and Frank Burns being section 8 after indecent conduct on R&R after Houlihans marriage, at the start of season six).

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