After retiring from the NFL, Greene spent one year (1982) as a color analyst for CBS’ NFL coverage before becoming an assistant coach under Steelers’ head coach Chuck Noll in 1987. He spent the next 16 years as an assistant coach with the Pittsburgh Steelers, Miami Dolphins, and Arizona Cardinals. In 2004, he retired from coaching and was named the special assistant for player personnel for the Steelers. In this position he earned his 5th Super Bowl ring after the Steelers won Super Bowl XL, and a sixth from Super Bowl XLIII. Greene is one of four people outside the Rooney family to have Super Bowl rings from the first six championship teams. Greene retired from his position in the Steelers’ front office in 2013.

It was Greene, in fact, who coined the phrase “One for the Thumb in ’81” after the Steelers won Super Bowl XIV. After the Steelers missed the playoffs in 1980, the saying was shortened to “One for the Thumb” and became the unofficial rally cry for the Steelers’ search for the elusive fifth Vince Lombardi Trophy until the team finally won it in 2005.

On July 30, 2014, it was announced that the Steelers would be retiring Greene’s No. 75, and it was officially retired at halftime during the Steelers game against the archrival Baltimore Ravens on November 2, 2014, a game the Steelers won 43–23. Greene was inducted into the Pro Football Hall of Fame in 1987. Greene now resides in Texas.