Complex sentence: SFRA awarded her the Thomas D. Clareson Award for Distinguished Service in 1997, and she has been a member of the panel for the John W. Campbell Memorial Award for best SF novel since 1986.
Split into simpler sentences: SFRA awarded her the Thomas D. Clareson Award for Distinguished Service in 1997. She's served on the panel for the John W. Campbell Memorial Award for best SF novel since 1986.