Alex King has vowed Saints will come back even stronger next season after delivering the double at Twickenham.
An Alex Waller try in the dying seconds of extra-time secured a 24-20 win against Saracens and first Premiership title.
That added to the Amlin Challenge Cup triumph, which came in Cardiff eight days earlier, making it the most memorable of seasons for Saints.
But attack coach King has pledged that Northampton will not rest on their laurels in the bid to keep the success story going next season.
He said: “We just want to kick on now.
“The guys have gone off on England tour in good spirits, but rugby is a pretty brutal game. We need to get back in July and reassert what we want to do.
“We want to kick on because as soon as you think you’ve made it, this game catches up with you and you don’t have any right to keep being successful.
“We’ll enjoy it for a couple of weeks but come next season we’ll concentrate on what we need to do to get better.”