On October 17, 2000, Dan scored his first career NHL goal against Andrew Raycroft and the Boston Bruins in a 6-1 Oilers victory.

Lacouture had his most productive season, scoring six goals along with eleven assists, and playing in all 82 games in 2001–02.

On February 10 of that year he was traded along with Alexei Kovalev, Janne Laukkanen, and Mike Wilson to the New York Rangers in exchange for Joel Bouchard, Richard Lintner, Mikael Samuelsson, Rico Fata, and cash.

He was called to Albany River Rats, but left the club on December 27, 2008, and signed a contract with Barys Astana of the KHL.

[citation needed] On April 10, 2014, LaCouture was revealed as one of nine former NHL players to file a major class action lawsuit against the NHL, alleging that the league has generated billions of dollars while subjecting its players to "the imminent risk of head trauma" leading to "devastating and long-term negative health consequences.