The Executioner (a.k.a. Mack Bolan) is a monthly men's action-adventure paperback book series (published from 1969 - 2020) following the exploits of the character Mack Bolan and his wars against organized crime and international terrorism. The series has sold more than 200 million copies since its 1969 debut installment, War Against the Mafia.

The regular series includes 464 novels (as of December 2020 when the series ended). Every other month, the Executioner series was complemented by the release of a Super Bolan, which were twice the length of a standard Executioner novel. There were 178 "Super Bolans" (as of December, 2015 when that series ended).

The Executioner was created and initially written by American author Don Pendleton, who penned 37 of the original 38 Bolan novels (he did not write #16). In 1980, Pendleton licensed the rights to Gold Eagle and was succeeded by a collective of ghostwriters. Some Pinnacle printings in the middle of Pendleton's original series carried a photo and brief article on the author, showing that Pendleton was not just a "house name".

Pinnacle Books was bought by Kensington Publishing (Zebra Books and others), and retained the rights to the original 38 novels; they were briefly reissued in the late 1980s-early 1990s.

Since its inception in 1969, The Executioner series has spawned several spin-off series including Able Team (1982), Phoenix Force (1982), and Stony Man (the series into which Able Team and Phoenix Force were eventually merged in 1991). The Stony Man series began in 1991 with "Stony Man" #2 (since the first "Stony Man" novel was published as a one-shot back in 1983, titled "Stony Man Doctrine" which is also regarded as the first "Super Bolan" novel).