Ben Thornley
Managing Partner
Ben Thornley is Managing Partner and Co-Founder of Tideline, where he leads the firm’s strategy consulting practice. Since Tideline’s inception in 2014, Ben has advised more than 150 institutional asset owners and managers on the design
and implementation of investment strategies that integrate impact and sustainability throughout the investment process. Collectively, these investors have deployed more than US$250 billion in impact capital, helping to shape the
evolution of impact investing from a niche practice to a mainstream investment discipline.
Ben is also Co-Founder of BlueMark, the leading provider of impact verification and intelligence. In 2024, Private Equity International named him one of the 50 most influential figures in sustainable private markets.
Widely recognized as a thought leader in impact investing, Ben has spent more than two decades at the forefront of the field’s development. Prior to Tideline, he led the pioneering research and consulting practice at Pacific Community Ventures (PCV), one of the earliest impact investing fund managers. There, with
support from the Rockefeller Foundation and in partnership with Harvard University, he founded the Impact Investing Policy Collaborative—a global network of researchers, investors, and policymakers spanning more than 30 countries. This work culminated in a White House invitation to deliver the first
expert presentation to the Social Impact Investment Taskforce convened under the United Kingdom’s G8 Presidency in 2013.
Ben has authored and contributed to numerous publications that have helped define industry best practices. Most recently, he co-authored The State of Market Institutionalization with the Institutional Limited Partners Association (ILPA). He
is also co-author of The Impact Investor: Lessons in Leadership and Strategy for Collaborative Capitalism (Jossey-Bass, 2015), widely regarded as one of the foundational books in the field.
Ben began his career as a financial journalist, serving as New York correspondent and Managing Editor for publications covering Australia’s institutional investment industry. He later moved into government, leading Australia’s efforts
to promote financial services trade and investment from the New York Consulate-General.
Ben holds a Master of Public Policy from the University of California, Berkeley. He serves on the Mission Alignment Committee of Azolla Ventures, an early-stage climate technology investor, and has guest lectured at Duke University, New York University, Columbia University, and Stanford University.
Born in New Zealand, raised in Australia, and now based in Portland, Oregon, Ben brings an international perspective to his work with investors and market builders across the globe.