The Alouettes set a team record for wins, but lost in the Eastern Division Finals to the Toronto Argonauts.

In 2000, he moved back to the United States and was the offensive coordinator of the Los Angeles Xtreme who went on to win the XFL Championship.

In 2002, Barker was hired to serve as an in-studio analyst on the America One's CFL telecasts,[3] but instead joined old boss Don Matthews as offensive coordinator and quarterback coach of the Montreal Alouettes, leading them to their first Grey Cup in over 20 years.

Quarterback Anthony Calvillo enjoyed his finest season as a pro and was the Terry Evanshen Trophy winner as Eastern Division Player of the Year.

He acquired Henry Burris, Jeremaine Copeland, Rahim Abdullah, and Sandro DeAngelis and played a role in the 2005 CFL Draft, selecting players such as John Comiskey, Brett Ralph, and first overall pick Miguel Robede.

After leading the Argos to the playoffs for the first time since 2007, Barker assumed the role of general manager on December 15, 2010, replacing Adam Rita, whose contract was not renewed.

Prior to the 2012 CFL season, Barker made a trade that brought All-Star quarterback Ricky Ray from the Edmonton Eskimos to Toronto to help an offense that had struggled for some time.

[6] Following the departure of June Jones just prior to 2019 training camp, Barker also added the title of offensive assistant for the 2019 season.