As a young man, Macchio was a comics fan and "letterhack," and had many letters printed in Marvel comic books. His background, however, was in English literature, and he considered teaching as a career. In no hurry to get such a job, Macchio happened to meet Killraven writer Don McGregor at a comic book convention.

Knowing Macchio from his many letters, McGregor asked Macchio if he wanted a tour of the Marvel offices. During the tour, Macchio was asked by writer Chris Claremont to interview editor-in-chief Roy Thomas for FOOM (Marvel's self-produced fanzine). During the course of doing the interview, Macchio met many more Marvel employees, and eventually was asked by writer/editor John Warner to join the staff and assist Warner with Curtis Magazines, Marvel's black-and-white magazine line, which included Doc Savage, Planet of the Apes, Marvel Preview, and The Deadly Hands of Kung Fu. Macchio, having "nothing else to do after graduate school," agreed and has been at Marvel ever since.

Writing

Macchio's most consistent early credits were as writer of Marvel Two-in-One, which he co-scripted with Mark Gruenwald from 1978 to 1981; and Thor, which he wrote (also with Gruenwald) from 1980 to 1981. Macchio shifted to mostly editing in 1982, though he wrote the scripts for the 1985-1986 The Sword of Solomon Kane mini-series, based on Robert E. Howard's Puritan swordsman; and had a stint as writer for Avengers in 1987 to 1988, and parts of 1989. He has also written for Marvel Fanfare and X-Men Adventures, and the premiere issue of Transformers, among others.

Editing

After working as an assistant editor for Warner on Curtis Magazines (Marvel's black-and-white magazine line), Macchio became Dennis O'Neil's assistant editor. Graduating to full editor in 1981, Macchio's first major editing job was Master of Kung Fu, which he helmed from 1982—1983. His first line of books was The Saga of Crystar (which he co-created with John Romita, Jr. and Mark Gruenwald), Dazzler, ROM, U.S. 1, and Micronauts. (During this early period, Macchio's assistant editor was Bob Harras, later to become Marvel Editor-in-Chief).

From 1984 through 1995, Macchio was Daredevil editor. He also spent close to ten-year stints on Thor and Captain America, and shorter periods on Avengers and Fantastic Four. Along way he edited movie adaptations, Star-Lord, and personal favorites like the barbarian book Kull the Conqueror.

In 1996, Macchio took over the Spider-Man line, which he helmed into the early years of this century. Since 2000, he has edited the entire Marvel Ultimates line.

In 2007, Macchio oversaw the adaptation of Stephen King's Dark Tower novels into a comic book series. (Macchio is a long-time fan of King's work.)

Jim Shooter (former Marvel editor-in-chief), writing about Macchio's job as editor of Moon Knight:

The satisfactions of being an editor:

The high points of his Marvel editing career:

His long tenure at Marvel Comics: