He played college football for the Georgia Tech Yellow Jackets and was selected by the Jacksonville Jaguars in the second round of the 2004 NFL draft.

[7] On November 28, 2010, Smith became the Jacksonville Jaguars all-time leader in tackles, surpassing former safety Donovin Darius.

Smith signed a one-year contract with the defending Super Bowl XLVII champions Baltimore Ravens on June 5, 2013.

[8] The signing was meant to strengthen the Ravens' inside linebacker core following Ray Lewis' retirement, and losing Dannell Ellerbe to free agency.

On December 9, 2013, he broke Ray Lewis' franchise record for most pass deflections in a single season (17) with 19.

[5] Archived September 25, 2013, at the Wayback Machine On March 14, 2014, his 32nd birthday, Smith re-signed with the Ravens on a four-year, $16.1 million contract.