D. Scott Barbour has served as a Director of Allison Transmission Holdings, Inc. since May 2022. Mr. Barbour serves as the Chief Executive Officer and President of Advanced Drainage Systems, Inc., or ADS, a manufacturer of water management solutions in the stormwater and on-site septic waste water industries, a position he has held since September 2017. Under Mr. Barbour’s leadership, ADS completed a transformative acquisition in an adjacent market and repositioned itself as a pureplay water management company. Mr. Barbour refocused ADS’ resources and capital on operational improvements to drive customer satisfaction and continuous improvement, while also building out the marketing, product development and material science capabilities of the company. Mr. Barbour has also overseen the establishment of the ADS Foundation, giving the company an avenue to provide assistance and education to causes that align with its Environmental, Social and Governance priorities, water recycling and community. From 1989 until 2016, Mr. Barbour worked for Emerson Electric Co., or Emerson, a global technology and engineering company that provides solutions for customers in industrial, residential and commercial markets as President and CEO of its $4.5 billion Network Power business. During his tenure at Emerson, Mr. Barbour also held several leadership positions including Group Vice President of Emerson Climate Technologies, President, Emerson Climate Technologies Asia Pacific Division, and President, Emerson Climate Technologies Air Conditioning Division. Mr. Barbour received his Bachelor of Science in Mechanical Engineering from Southern Methodist University and his Master of Business Administration from the Owen Graduate School of Management, Vanderbilt University. Mr. Barbour serves on the board of directors of ADS.