Olson was offensive coordinator and quarterback coach at Central Washington University from 1990-1993, where he coached 16 year NFL veteran quarterback Jon Kitna. While at Central, Olson also coached the university's wrestling team. Prior to joining the CWU coaching staff, he was a graduate assistant at Washington State University for three seasons. He coached the defensive backs at WSU for one season and was the linebacker coach for two years. He also coached running backs at Spokane Falls Community College in 1986. After leaving CWU, Olson coached quarterbacks at Purdue University, where he played a key role in the development of future Pro Bowler and Super Bowl-winning quarterback Drew Brees. Under Olson, Brees was a Heisman Trophy finalist in 1999 and 2000 while winning the Maxwell Award as the nation's most outstanding player in 2000.
Olson previously served as the quarterbacks coach of the Detroit Lions, where he worked with Joey Harrington. He served as Lions offensive coordinator following the firing of Steve Mariucci and the demotion of Ted Tollner during the 2005 season.
He was the offensive coordinator of the St. Louis Rams from 2006-2007. In his first year with the Rams in 2006, he helped guide a high-powered offense that ranked sixth in the NFL in total offense (360.4 yards per game) and a passing offense that ranked third (247.6) in the NFC. Under Olson's direction the Rams became just the fourth team in NFL history to produce a 4,000 yard passer (Marc Bulger), a 1,500 yard rusher (Stephen Jackson) and two 1,000 yard receivers (Torry Holt and Isaac Bruce). Bulger, Holt and Bruce were all selected to the Pro Bowl. Bulger also posted career-highs in passing yards (4,301), passing touchdowns (24), and passing attempts (588) and completions (370) while ranking second in the NFL in interception percentage (1.4%). Jackson also had a career-year in 2006, leading the NFL in yards from scrimmage with 2,334, and he led all NFL running backs with 90 receptions and was fifth in the NFL in rushing yards with 1,528.
In January 2008, Olson was hired by the Tampa Bay Buccaneers to be their quarterbacks coach following the dismissal of Paul Hackett. On September 3, 2009, the day before the team's final preseason game, the Buccaneers announced that Olson would replace Jeff Jagodzinski as Offensive Coordinator. Olson was responsible for the development of QB Josh Freeman, the 17th overall pick in the 2009 draft. Under Olson’s guidance, Freeman threw for 8,898 yards and 51 touchdowns in his first three seasons as a starter. In 2011, Freeman ranked eighth in the NFL with a 62.8 completion percentage and 13th with 3,592 passing yards. In Olson’s second season as offensive coordinator with the Bucs in 2010, Freeman ranked sixth in the NFL with a 95.9 passer rating while throwing for 3,451 yards, 25 touchdowns and only six interceptions. Olson helped guide the Buccaneers to one of their best offensive seasons in team history, setting franchise records for yards per play (5.61), average per rush (4.64 yards), average per pass play (7.21), passer rating (96.2) and fewest interceptions thrown (six). The Buccaneers also finished with the fourth-most points scored (341), third-most yards in total offense (5,362) and second-best third down percentage (42.2%) in a single season in team history.
The Buccaneers were the youngest team in the NFL in 2010 and WR Mike Williams, a fourth-round draft pick, finished the year leading all rookie receivers in the league in every major receiving category while setting a single-season team record with 11 touchdown receptions. RB LeGarrette Blount’s 1,007 rushing yards led all rookie running backs and he became just the second undrafted rookie running back in NFL history to finish with over 1,000 yards. It marked the first time since 1968 that a team had two different players lead all rookies in rushing and receiving yards. He was fired on January 2, 2012, after his team posted a 4–12 record.
In January 2012, Olson was hired to be the Assistant Head coach/quarterbacks coach for the Jacksonville Jaguars.
In January 2013, Olson was hired to be the offensive coordinator of the Oakland Raiders, taking over for the recently fired Greg Knapp.
In 2014,Olson was fired as offensive coordinator of the Oakland Raiders
On January 21, 2015, Olson was hired to be the offensive coordinator of the Jacksonville Jaguars.
On October 29, 2016, Olson was fired from Jaguars following a loss to the Tennessee Titans.
On January 18, 2017, it was announced by the Los Angeles Times that Olson would be hired by the Los Angeles Rams to serve as quarterbacks coach.
Olson is a 1981 graduate of Richland High School. At Richland, he lettered in football, baseball and wrestling. In football, he earned all-conference honors at quarterback and linebacker.
He played two seasons at Spokane Falls, earning all-conference quarterback honors in 1982, prior to transferring to Central Washington University in Ellensburg, Washington. He earned a BA degree from CWU in 1986 and a MS in physical education from Washington State in 1990