Mark McDonnell has served as ARCH Venture Partners' Managing Director, Chief Financial Officer, and Chief Administrative Officer since 1999, giving him unusually broad responsibility for developing limited partner strategies, managing strategic relationships, and directing both the firm's operations and portfolio company financing infrastructure. Beyond his operational role at ARCH, he serves on the board of the Illinois Venture Capital Association and brings multi-firm venture CFO experience from his previous role at Marquette Venture Partners, positioning him as a long-standing anchor figure in the Midwest venture ecosystem.