Mary Sullivan has become the new president of the Civil Service Employees Association, one of the largest public-sector labor unions in the state.

Sullivan is succeeding Danny Donohue, who announced this summer he was stepping down from the post he has held for the last 25 years.

She is the second woman to fill the president’s office at the union. She will serve out the remainder of Donohue’s term, which runs until Feb. 29 next year.

“I’m proud to be leading our great union forward as president,” Sullivan said. “Under my leadership, we will build on our many accomplishments, be even more inclusive, and even more engaged with our members.”

Sullivan as been a union activist for 35 years, starting as an employee in the Herkimer County Department of Socail Services. She served for 25 years as the union’s executive vice president.