2025 40 Under 40: Millie Tolleson

Millie Tolleson, director of planning, San Mateo County Transit District (SamTrans), began her transit career as an intern at the San Francisco County Transportation Authority and went on to spend nearly three years at Nelson\Nygaard, where she led and supported diverse projects—from regional late-night transit planning to youth mobility strategies and transit demand management evaluations. She also served as an embedded consultant managing the US-101 Express Bus Feasibility Study at SamTrans.  

Tolleson joined SamTrans as a principal planner, was promoted to manager of strategic planning and now serves as director of planning, managing a team of 16. With each role, her leadership and influence have grown. Her leadership includes planning for the use of zero-emission buses in areas with the highest asthma rates, greenhouse gases and particulate matter, as well as championing the inclusion of shade structures and shelters at bus stops in high heat vulnerability areas. 

She championed the implementation of Reimagine SamTrans, the agency’s comprehensive service redesign, which has resulted in customer satisfaction and ridership levels surpassing pre-pandemic levels. She also led the launch of on-demand transit in equity priority areas and expanded youth and institutional fare programs that improve transit access and affordability.  

Tolleson developed the agency’s new strategic plan, establishing an updated mission, vision and set of key initiatives for the next 10 years. As project manager for Reimagine SamTrans, she led a complete service redesign that increased frequency, expanded evening and weekend service, streamlined routes and introduced on-demand transit—all grounded in data and community feedback. She advocated for partnering with and compensating community-based organizations to lead outreach, ensuring that historically underserved voices were at the center of the planning process.  

She also developed the Service Policy Framework and established Equity Priority Areas, helping the agency define where service is most needed and guiding future investment into those areas. Tolleson championed a comprehensive study of restroom access for SamTrans bus operators, which led to the introduction of an innovative partnership to provide mobile operator restrooms. 

Tolleson contributed to the 95th Annual Transportation Research Board meeting with a paper titled “Congestion Pricing and Strategies for Affordable Mobility on Treasure Island” and represents SamTrans in regional planning efforts led by the Metropolitan Transportation Commission, where she collaborates with transit agencies throughout the Bay Area to improve systemwide connectivity. Colleagues say her leadership in these efforts has supported initiatives like fare integration and fare capping in an effort to make transit more affordable for riders who rely on multiple providers to complete their trips. 

She holds a bachelor's degree in communications, journalism and public relations from Appalachian State University and a master’s degree in transport and city planning from University College London.  

Is there a specific experience that led you to where you are today? 

 Early in my career, I worked in community development and was exposed to the concept of servant leadership. Today, as a team leader, I use what I learned to act in service as a leader to my team, seeing my role as smoothing the path for them to do their best planning work and doing my best to get them the resources and support they need.    

What do you enjoy most about your job?  

Hands down the moments I still get to work closely with members of the incredible SamTrans planning team to solve a tricky problem or improve a program that benefits our customers and our community. I love mentoring and supporting members of my team to do their best work, and it doesn’t get better than finding out you made someone’s life easier by providing high quality, reliable transit service.   

What’s the most challenging part of your job?  

The challenging moments are the ones when we must make trade-offs in terms of where to put our operating resources and explain our decisions to the community. However, taking the time to explain and educate people—and creating policies we can lean on later when the trade-offs get tough—makes it easier.   

 What is the accomplishment you’re most proud of and why?  

I am proud to have been the project manager of our Reimagine SamTrans systemwide COA, which took in thousands of pieces of community input and utilized travel data as it evolved in real time in 2020-2022. During this time, our project team bravely and safely continued doing robust public outreach to make sure we heard from the community in redesigning our bus system. Today, SamTrans is enjoying 105 percent of pre-pandemic ridership, at least partly because of our responsive transit planning.   

What is your best advice/tip/best practice you can share from your area of expertise?   

Stay away from the noise. Stay focused on your goals and the positive impact you can have on people’s lives. It’s very rewarding to serve the public. It’s also difficult work. Take care of yourself, rejuvenate and stay focused. Oh, and if you work in transit, you need to ride transit.