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Since 1982, Mr. Bigras has spent his career in the construction, cleaning and facility maintenance industry. He joined GDI in 1994 and later became a major shareholder in 1998. Over the years, he has held many positions and became President and CEO of GDI in December 2004. In his role as President and CEO, Mr. Bigras has overseen GDI’s significant organic and acquisition-based growth, leading GDI to become the largest facility services company in Canada and one of the largest in North America.
Mr. McGuire is President and Chief Operating Officer, Business Services Group since May 2025. From 2022 until June 2024, he was a valuable member of the GDI Board of Directors. Over the past 25+ years, Mr. McGuire has held senior-level leadership positions in the financial services sector, including notable roles at Goldman Sachs and J.P. Morgan. More recently, he ran Longwing Partners LLC, a private consulting firm specializing in strategic advisory services.
Steve Heiderstadt has over 40 years of experience in the HVAC service and mechanical contracting industry, beginning his career as a field service technician and progressing through estimating, project management, department leadership, construction management, and senior executive roles. He spent more than three decades with BP Air Conditioning and its affiliated companies, playing a pivotal role in scaling the organization into one of the premier mechanical contractors in the tri-state area, which was acquired by Ainsworth in 2021. For the past decade, Steve led the New York City office, overseeing complex, multi-disciplinary operations and high-profile projects.
Today, Steve serves as Senior Vice President of Ainsworth Mechanical–New York, providing strategic leadership across HVAC operations, financial oversight, contract compliance, and team development. He works closely with executive leadership to ensure alignment with organizational values and goals while fostering strong client relationships. Steve is a professional member of ASHRAE and several industry associations, and a graduate of Babson College’s Advanced Leadership Institute.
Dawn Criville is a senior sales and business development executive with more than 30 years of experience driving strategic growth and client partnerships across the financial services and facility services industries. She currently serves as Executive Vice President of Business Development, US for GDI Integrated Facility Services, where she leads national sales initiatives and business development strategy across multiple industry verticals.
Prior to joining GDI, Dawn served as Vice President of Mergers & Acquisitions at Citigroup, specializing in middle market M&A transactions. Throughout her career, Dawn has been recognized for building strong client relationships, leading high-performing teams, and driving transformational growth.
Dawn earned both her MBA in Finance and Bachelor of Science in Accounting from Widener University.