Northampton 13 Wasps 30: Wasps survived a major semi-final scare at the Ricoh Arena before booking their place in this season's Heineken Cup final.
The 2004 European champions will meet fellow English heavyweights Leicester at Twickenham on May 20th - the first all-English Heineken final - after fighting back from 13 points adrift to deny Northampton a famous victory.
Saints, who stunned French giants Biarritz in the quarter-finals, raced 13-0 clear through skipper Bruce Reihana's try, conversion and two penalties, capitalising on a strangely error-strewn Wasps display.
But Lawrence Dallaglio's men finally stirred, going ahead for the first time after 60 minutes when Dallaglio's replacement James Haskell ploughed over for a close-range try.
Wing Paul Sackey had earlier touched down, while full-back Mark Van Gisbergen kicked two penalties, before Sackey's second try, converted by Van Gisbergen - and a converted Josh Lewsey score - sealed the deal.