Akos, who has been with the FWSO for two years, will leave when her contract expires on April 1.
"Since planning for the 2007-2008 season is well under way, I believed it would be in the best interest of the symphony to inform its executive committee of my decision at this time," Akos said.
William P. Hallman, chairman of the association, said, "We wish Kate the best. Since her appointment in 2004, the orchestra has achieved a new level of artistic excellence and financial stability. During the past two seasons, we have seen increased contributions, with an all-time high of $5,540,000 raised in annual support for the 2004-2005 season."
No official reason was given for the resignation, but according to the Fort Worth Star-Telegram, it has been rumored that Akos had a frosty relationship with the symphony's music director, Miguel Harth-Bedoya, and with the heads of other local performing arts groups.
Akos, a professional violinist, was the Detroit Symphony Orchestra manager from 1985 to 1987, and the San Francisco Symphony's assistant manager from 1987 to 1991. Ann Koonsman, who retired as the symphony's executive director in 2004, has been appointed executive director on an interim basis.