Ann Evans, who has been executive director of the Lawrence Arts Center since it opened in 1974, announced today that she will retire from the post.

Her last day will be Dec. 31.

“I decided it was time for me to figure out what the next phase of my life is going to be,” said Evans, who turns 61 in December.

Evans informed the arts center board of her decision at its meeting this morning.

Under her leadership, the community hub for the arts grew from offering 20 classes to 240 students annually to offering 450 classes to 8,500 students. Evans also oversaw expansion of the center from the half-renovated Carnegie building in 1974 to the state-of-the-art facility it now occupies in the 900 block of New Hampshire Street.

The board will reconvene Friday morning to discuss the appointment of an interim director and the launch of a national search to hire Evans’ replacement, said John Olson, board member and past president.

He praised her leadership over 33 years.

“She’s been iconic,” Olson says. “When you think of the arts center, you think of Ann Evans. The two are intertwined forever.”