During an afternoon news conference making his hiring official at the Bowling Green school, Petrino was asked what he's done since leaving Arkansas.
"I've basically spent the last eight months trying to make things right with my family," he said, noting that he and wife Becky have been in counseling, where he "learned a lot about himself."
Petrino was fired by the University of Arkansas in April after being hurt in a motorcycle wreck that led to the discovery of an extramarital affair with his passenger, Jessica Dorrell, a 25-year-old athletic department worker who Petrino had personally hired.
Petrino told reporters his acceptance of the job was "a family decision" and that he's "extremely grateful to be given the opportunity to be Western Kentucky's football coach," saying further that "my vision is to take it to the next level."
Of Petrino's hiring, WKU Athletic Director Todd Stewart said he was the best choice. "Coach Petrino was No. 1. When you can get No. 1, you do everything to get No. 1."
Petrino's four-year contract with WKU has a base salary of $850,000.