He earned an appointment to West Point, but transferred to Bowling Green State University a year later to pursue coaching.

In 1967, he joined Bo Schembechler's staff at Miami University, serving as defensive end coach for two seasons.

Tulane lost to Penn State, 9–6, but Smith's ability to finish the season 9–3 attracted attention and he was hired away by Arizona.

[4] Under his guidance, 10 Tulane players earned All-America honors, including two-time All-American quarterback Roch Hontas and kicker Eddie Murray, as well as offensive tackle Eric Laakso and tight end Rodney Holman.

Smith put great emphasis on in-state recruiting, built up the rivalry game with ASU, and focused the team on what he called "running and hitting".

The highlight of the season was a 23-17 upset of 2nd-ranked UCLA (the Bruins were poised to become #1 as top ranked Alabama had lost earlier in the day).

[6] After success at Tulane and Arizona, Smith was hired as USC's first coach without previous Trojan ties since Howard Jones in 1925.

[2] Smith's USC team entered their final regular season game ranked #2 against the #1-ranked rival Notre Dame; the Fighting Irish defeated the Trojans, 27–10, en route to a national title.

Despite being heavy underdogs, the Trent Dilfer-led Bulldogs won in a 24–7 upset victory that angered many USC supporters.

Within days of the Freedom Bowl loss and his commentary, Smith was fired by USC with three years left on his contract.

[8] During his tenure he coached 13 All-American first teamers, including Heisman Trophy runner-up Rodney Peete, Thorpe Award-winning safety Mark Carrier, linebacker Junior Seau, wide receiver Curtis Conway and defensive tackle Tim Ryan.

[16] Smith was rewarded at the end of the 1998 regular season with a new five-year contract that raised his salary from $161,500 to $180,000 annually; he had become one of just four coaches in NCAA history to take four schools to bowl games.

[18] After his coaching career ended, Smith moved back to Tucson and worked as a commentator for Arizona football games on Fox Sports Net, and organized weekend instructional camps twice annually.

[5] Corby Smith played at quarterback for both USC and Iowa, graduating from the latter in 1995 and immediately joining his father on the coaching staff of Missouri.