Longford will meet Bohemians in the final of the eircom League Cup after this tactically inspired victory ended First Division Harps' 13-match unbeaten run.
Harps enjoyed much of the ball but fell behind to a classic counter attack on 18 minutes. Tony Gorman lost out to Dessie Baker who sent Sean Prunty away to cross for Sean Francis to tap in.
Darragh Sheridan chipped against the Harps' bar on 45 minutes before Town did double their lead within ten minutes of the restart.
Keeper James Gallagher spilled a cross and Baker stole in to shoot into an unguarded net. Kevin McHugh gave Harps hope when hitting back two minutes later, but Town defended well to reach their third cup final in 12 months.
