Douglas Hyland, who has led the New Britain Museum of American Art through two major expansions, tripled its collections and more than doubled its endowment, will retire as the museum's director after its new addition is complete next fall.

Hyland, 65, announced his decision Wednesday at a meeting of the museum's board of trustees.

"Everything I envisioned for this museum has been accomplished," Hyland said. "The collections have grown, the attendance is at 100,000. This is the best year of our history."