The NHL locked out its players at midnight Saturday, becoming the third major sports league to impose a work stoppage in the last 18 months.
The action also marks the fourth shutdown for the NHL since 1992, including a year-long dispute that forced the cancellation of the entire 2004-05 season when the league held out for a salary cap.
The deal which ended that dispute expired at midnight, and Commissioner Gary Bettman followed through on his pledge to lock out the players with no new agreement in place.
NHL Deputy Commissioner Bill Daly said the lockout was effective at 12:01 a.m. Sunday.
The main issue is money - how to split $3.3 billion in revenue.
The sides were so far apart in their discussions that they didn't meet face-to-face for negotiations on Saturday.