Our Staff


Seth Millican

Executive Director

Prior to joining the Georgia Transportation Alliance, Seth worked as Vice President of Public Affairs at Brock Clay Government and Public Affairs. He began his career working in various staff positions in the Georgia General Assembly. Seth earned his B.S. in Social Sciences from Thomas Edison State College. He’s married to his high school sweetheart, Kara, and they have three children: KJ, Eden Grace, and Gabriel. Seth loves Georgia sports teams, hunting, books and writing (on politics and culture), his faith, and his family.

Seth has been recognized in various publications for his work on behalf of political causes and policy related initiatives. He was appointed by Governor Nathan Deal to Chair the Georgia Athletic and Entertainment Commission and also serves on the board of the Georgia Wildlife Federation. He is also a founding member of the American Road and Transportation Builder’s Association Transportation Investment Advocacy Center, co-chair of the Council of State Chamber’s Transportation Committee, a member of the American Enterprise Institute’s Leadership Network, and a member of the U.S. Chamber’s Transportation Infrastructure and Logistics Committee


Maddison Hendershot

Director of Operations

Maddison graduated with Honors from Samford University with a Bachelor’s Degree in Human Development and Family Life Education. After graduation, Maddison returned home to Atlanta and began her career. Maddison serves as the Director of Operations for Georgia Transportation Alliance focusing on board engagement and events throughout the year. Maddison married to her college sweetheart, Nathan. They live in Alpharetta, GA, attend North Point Community Church, and have a loving, rescue puppy named Hoosier.


Allison Plummer

Government & Political Affairs Manager

Allison Plummer started at the Georgia Chamber on the Public Affairs Team in July of 2018. Allison organizes events and communications for the Chamber’s Political Action Committee and Government Affairs Council. Prior to joining the Chamber, Allison coordinated political campaign fundraising efforts for Geoff Duncan for Lieutenant Governor. Before working on the campaign trail, Allison started her career in Washington, DC, serving as Staff Assistant & Press Assistant for US Congressman Austin Scott (GA-08).

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