Dowson has made 125 appearances for Newcastle
Newcastle captain Phil Dowson has signed a two-year deal with Northampton that will take him to Franklin's Gardens for the start of next season.
The move will mark the end of an eight-year spell with the Falcons for the 27-year-old back-rower.
"I need to get out of my comfort zone and develop as a player and this move to Northampton will do that," he said.
"Over the next few years I want to help the Saints push up the Premiership and hopefully win some silverware."
Dowson, who has been club captain at Kingston Park for the past two years, also skippered England Saxons to Churchill Cup victory in 2007.
That campaign brought him under the leadership of Saints director of rugby Jim Mallinder, who is certain he will add something new to the Northampton pack.
"The back row is a vital area of the game and Phil's know-how, skills and physicality will complement the players we have here already superbly," he said.
"Phil is an exciting signing for us as we build for next year. We want leaders at the club who will represent us well on and off the field and Phil is one such man."
Dowson won the Premiership try of the season award in 2004 and 2005 and crossed for a consolation score in his side's 32-13 European Challenge Cup loss against Saracens on Sunday.