Matthew Williams is a volatilization to indoor air specialist with the Michigan Department of Environment, Great Lakes, and Energy (EGLE), Remediation and Redevelopment Division. He leads development and implementation of vapor intrusion investigation, assessment, and mitigation methodologies to protect indoor air quality. As technical lead for EGLE’s Vapor Intrusion Technical Assistance and Support Team, he has authored key guidance, SOPs, and technical papers, and delivered extensive national and international training. Matt has held multiple leadership roles with the Interstate Technology & Regulatory Council and led the national vapor intrusion guidance update, recently released, and currently serves on the Board for the Association of Vapor Intrusion Professionals (AVIP).