Mary Hallahan enters her fifth season with the Sewanee volleyball program in 2023. 

In 2023, the AVCA recognized her as a part of the "Thirty Under 30" coaches program, which celebrates up-and-coming coaches at all levels of volleyball—college, high school and club—and the recipients serve in a range of roles, from head coach to volunteer assistant to club director. 

Prior to her arrival on the Domain, Hallahan served as a volunteer assistant coach for King University in Bristol, Tenn. for the 2018 season. At the NCAA Division II institution, she was responsible for practice planning and execution, film breakdown, game planning and organizing travel plans. On the court, she led service receptions, defensive schemes and individual setting techniques.

Before she began her coaching career at the collegiate level, she served as a varsity assistant coach with North Oldham High School in Louisville, Ky. She was also the head coach of the junior varsity squad during the 2017 season.

In club volleyball, Hallahan works with A5 Chattanooga and has previously worked with Kingsport Volleyball Club, Union Volleyball Club, Kentucky-Indiana Volleyball Club and the Orlando Volleyball Academy.

Coaching volleyball since 2011, Hallahan graduated from the University of Central Florida in 2014 with a Bachelor of Science in Criminal Justice.

Updated 5/24/23