North helps Northampton take top Premiership spot
Rugby player George North warms up during the team captain's run in Sydney on July 5, 2013
After a hard-fought first half ended level at 6-6 following two penalties apiece from Northampton's Stephen Myler and Quins' Nick Evans, it was time for North to take over.
North provided the stand-out moment four minutes into the second half when he caught a poor clearance and raced along the touchline and into the left corner for a superb individual try, bumping off a tackle from opposite number Charlie Walker in the process.
Ben Botica's penalty for the visitors made for a tense finish but Myler added a penalty and then a conversation after Dylan Hartley's try.
Northampton never relinquished control and they replaced Saracens, who face Gloucester on Saturday, at the top of the table.
In Friday's other match, Sale won 16-8 at Newcastle to end their dismal record at Kingston Park.
With just one win in their last 20 visits to the north east, Sale scored a crucial first half try through winger Tom Brady, while Danny Cipriani added a conversion and penalty.
However, former England star Cipriani did not enjoy a great return after missing last week's game because of flu and he was replaced in the second half by Scott MacLeod, who made sure of the win with a penalty seven minutes from time.
The win moves Sale into sixth place, while third bottom Newcastle remain embroiled in the relegation battle after failing to build on Andy Saull's try, which came just six minutes after Brady's strike.