Jacob Butterfield, James Collins and Harry Cornick all scored as Luton recorded their first Sky Bet Championship win of the season at Barnsley.
Mallik Wilks pulled a goal back for Barnsley during the second half but the Tykes could not swerve a 3-1 home defeat.
The visitors got off to a flying start with two goals in the opening five minutes.
Butterfield was the first to strike with a well-struck effort from the edge of the area two minutes in.
It was 2-0 three minutes later when keeper Sami Radlinger failed to cut out a cross, James Bree drilled in a low shot which was blocked and Collins was on hand to force the ball over the line.
Radlinger did well to prevent Collins from scoring his second goal of the match, turning the ball wide.
Barnsley's Alex Mowatt tried a long-range effort which went over and Wilks saw his shot from inside the area blocked.
Luton continued to apply pressure, however, with Cornick and Matt Pearson both having shots saved by Radlinger.
It was no surprise when the visitors added a third goal in the 31st minute as a free-kick was headed down and Cornick hammered the ball into the net.
Luke Thomas had an opportunity to reduce the arrears shortly before the interval when he received the ball inside the area but put his shot off target.
Barnsley boss Daniel Stendel made a double substitution at the start of the second half, with Jordan Green and Ben Williams replacing Mads Andersen and Daniel Pinillos.
The home side posed an attacking threat in the opening stages of the half, with Mamadou Thiam in the thick of the action, first heading just wide and then firing in a shot from the left-hand side of the area which was palmed wide by Simon Sluga.
Wilks (72) did find the back of the net, firing in after Mowatt played the ball across the box.
Cameron McGeehan just failed to get a touch to a Wilks header following a corner as the hosts went in search of a second to put themselves in contention.
Thiam spooned the ball well over from inside the area following Green's lay-off.
Barnsley, who beat Fulham on the opening day of the season, have now lost four of their last five games.
Daniel Stendel: "It was a big chance for us to take the second three points but our start was so bad with two goals after five minutes for Luton. We were insecure and it was hard. We were prepared for the game and the atmosphere yesterday was good but the start wasn't.
"You cannot play like this in the Championship and this was the big experience from the game. We need to apologise for the first half. The supporters can have expected more from us. We need to come back to our best performances. The most things you can learn in the worst situation. I learn things and we need to improve. I think we will do it."
Graeme Jones: "I couldn't be happier with where we are today. The boys have been magnificent - every single one of them. These characters are outstanding and you feel for them at times when they're giving everything they've got. The reward for the lads is a great feeling.
"I think we need to enjoy the win and the performance because we were ruthless at times and I mean ruthless. If we'd have been five-nil up at half-time, nobody could have complained. I knew we were really close but there comes a time when you have to win a game of football, no matter who you are. The psychological barrier was getting broken down week by week. I think we'll take a lot psychologically from it."