Who We Are

City Scale is a collective of former city sustainability practitioners. We come at this work from the world we know best: local government, where each of us spent a decade or more leading urban sustainability programs. We blend our practitioner experience with our current perspective working outside of government to take a step back, make sense of a bigger picture, and organize collaborative action. We’ve come to see this community of practice view as an uncommon and important vantage point to work from.

We work on projects together, separately, and with a range of collaborators. The similarities in our backgrounds give us depth but also create blind spots, and so we work in partnership whenever we can to bring different experiences, positioning, and skills to our work.

Katherine Gajewski

I love relational work: working in partnership and building coalitions. Bringing people together around shared purpose has been a consistent thread throughout my career–from community organizing to policy making. Before launching City Scale, I served as the director of sustainability for the City of Philadelphia. Toward the end of my decade in government, I started to see things I hadn’t been able to see earlier on, and began to ask questions that I and others couldn’t readily answer. City Scale has facilitated a learning journey for me, one that led me to take a “big think” year at the Harvard Kennedy School along the way. I’m developing my practice, which calls on different diagnostic tools and frameworks to try and see as much as possible. I recently moved to Chicago, where I spend a lot of time hanging out with my son and the preschool set, who constantly remind me that being curious and imaginative is the best way to be.


Michael Armstrong

I like a multi-dimensional puzzle and seeing individual issues and organizations as part of a larger landscape of issues, geographies, and time. In that spirit, I’m a big believer in building relationships for the long run. Prior to joining City Scale, I spent 17 years with the City of Portland managing the climate policy and programs for the Bureau of Planning and Sustainability, including developing three generations of climate plans for Portland and Multnomah County. Beginning in 2008 I played a variety of roles with national and international networks of local government sustainability staff. I have a longstanding interest in strengthening links between academia and practitioners and relished helping to build a partnership between Portland State University and the City of Portland. In the 1990s I spent five years in Namibia and South Africa; I now live in Portland, Oregon.


Ariella Maron

Ariella was a vital part of the City Scale team until 2023, when she took the role of Executive Director for the Delaware Valley Regional Planning Commission. We are excited to see Ariella tackle the crucial work that can only happen through regional governance and to learn from her along the way.

How We Got Here

City Scale started in 2016 with the intent to aggregate and accelerate city carbon-reduction projects. Since then, the world has changed, the work has changed, and so have we. We are grateful to the Summit and Surdna Foundations for providing the starting funding that allowed us to explore, learn, and change course during our incubation phase, and to the Innovation Network for Communities (INC), which generously serves as City Scale’s fiscal sponsor.

Collaborators and Funders

In addition to developing our own projects, we have been fortunate to work and partner with organizations across the field, including:

partners_0000_Surdna Foundation
partners_0001_The Summit Foundation
partners_0010_Bloomberg Philanthropies
partners_0004_Rockefeller Brothers Fund
sized logo PCC
sized logo City Energy

A scene from Katherine’s bike commute to her son’s school. Like many cities, Chicago is struggling to address the unequal burden of it’s active and transitioning industrial areas.