Callum Hendry was spot on again as St Johnstone sparked further life into their Premiership survival mission.
The in-form striker kept his composure from the penalty spot in the opening minutes to steer Saints in front.
And that effort from 12 yards proved to be the deciding factor in earning all three points at McDiarmid Park.
Continuity was the name of the game for Callum Davidson who was able to field the same starting team from the dramatic late win against Motherwell two weeks ago.
A similar result, albeit not leaving it quite as late, would be most welcome in the chase for Premiership safety.
The mission for maximum points started on the front foot and in the perfect manner when referee Kevin Clancy was pointing to the penalty spot in just the third minute.
Livingston defender Jack Fitzwater was the guilty man - his flailing arm catching Hendry deep inside the box.
The Perth forward, after picking himself up, kept his composure to steer the ball down the middle for an early lead.
Hendry has been a revelation since returning from his Kilmarnock loan and his goals of huge significance.
Of course he would go hunting for a second but Saints did soon have to fend off a couple of visiting attacks.
Alan Forrest first tried his luck with a strike that was never going to escape the grasp of towering Zander Clark.
And then the Scotland international goalkeeper was required to smartly stop an angled Sebastian Soto drive.
Perth boss Davidson needed to turn to his bench in the 35th minute when Tony Gallacher picked up a knock. He was replaced by Callum Booth.
Saints quickly recommenced the search for a second with Ali Crawford, a real livewire, forcing Max Stryjek into a clever save from a powerful low strike.
There was little excitement to report on in the early stages after the break but Nadir Ciftci, determined to make his mark, did have a sight of goal as the hour mark approached.
The forward edged in front of his man and, from Shaun Rooney’s delivery, flicked a header wide of the post.
As the game progressed, there was always a nervousness about the possibility of a Livingston equaliser.
Advanced defender Ayo Obileye attempted to level proceedings when the ball dropped into his path on the edge.
His strike was clean but well-positioned Clark was down quickly to keep out before home defenders swiped clear.
Fresh legs in Stevie May then entered the action in place of Ciftci with little over 15 minutes.
Livingston were livid in the closing stages when claiming the ball had struck the arm of Dan Cleary in the box. Nothing was given and the full-time whistle soon arrived.
Eleventh-placed Saints, six clear of basement boys Dundee, are now just six points behind both St Mirren and Aberdeen.
