Bart has headed the newsroom at Variety for 20 years. Variety said on its Web site late Sunday that Bart will become the publication's vice president and editorial director.
Veteran editor Tim Gray is taking over as head of the news operation, effective immediately.
Tad Smith, chief executive of parent company Reed Business, says an agreement has long been in place that Bart would step aside after 20 years and Gray would take over.
Bart will also continue to write a column and blog for Variety.