A fourth-generation Massachusetts farmer, Gillespie comes to the Department of Food and Agriculture from his most recent position as Assistant Executive Director for the Massachusetts Farm Bureau Federation in Ashland. He has been with the Farm Bureau since 1990 and has also served as Director of Member Relations and Director of Government Relations.

Gillespie is in his fourth year on the Weston Board of Selectmen and has been active on the State Commission for the Conservation of Soil, Water and Related Resources. He has also been a board member of the Weston Land Trust and Vice Chairman of the Recycling and Solid Waste Advisory Committee for the Town of Weston.

Gillespie resides with his wife Denise, who is the daughter of several generations of central Texas ranchers, and their son Seth in Weston.