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The extension of your family that makes you money.

Riverstone Advisors serves customers from all over the United States. The diversity of clients from across the nation makes our work fun and interesting.

We take pride in having dedicated our careers to mastering the skills necessary to build successful portfolios as well as to carry fiduciary duty with integrity. Our goal is to take the complicated task of managing your financial affairs off your plate so you can focus on enjoying your life, career, hobbies and/or family.

Leslie J. Lammers, CFA


Leslie founded Riverstone in 2004 to service client accounts she had managed since 1993. These clients are the bedrock of Riverstone today. She founded Riverstone to have the freedom to do the right job for clients. From Leslie’s perspective, portfolios should be tailored to an individual’s needs. Her ability to see, understand and analyze a market, demographic, or business trend has made the difference between hundreds and millions in investing success.

Leslie believes there are great investments out there, and it’s her job to find them. She calls this the “so many boys (girls) at the dance” concept. She loves discussing this concept with her clients.

Leslie is the Chief Executive Officer and Co-Chief Investment Officer of Riverstone Advisors. She is a CFA charter holder, a certification she is very proud to have, and lives in New Braunfels, TX.

When Leslie is not working, she enjoys spending time with family and friends, dancing, and listening to live music. She has been married to Tom forever and is blessed with two daughters and one granddaughter who is the most adorable girl in the world.

Giving Back

Communities in Schools

Communities in Schools of South Central Texas is a drop-out prevention program with a proven track record of success. In-school social workers work with school staff to address the needs of students. And when students stay in school they have a chance to live happy, healthy lives of contribution to the community.

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STEPS (Solutions That Equip People for Success)

STEPS is a program that gives individuals an opportunity for a better life. It was designed to help those who are willing to change, by equipping them with the tools, resources, and encouragement they need. At STEPS, we believe in the dignity and worth of every person. Our job is to locate hindrances, physical or otherwise, that stand between an individual and their success, and help them to rectify those hindrances however possible. STEPS not only looks at the immediate needs of the individual or family, but also at their long term well-being. The aim is to not provide a band-aid, but to provide long term solutions.

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John A. Hanson, CFA


John joined Riverstone in 2012 and is currently the Co-Chief Investment Officer and Portfolio Manager. An engineering graduate of the Georgia Institute of Technology, John brings a keen analytical eye to investment opportunities and financial planning scenarios.

Before joining Riverstone Advisors, John worked in investment banking at SunTrust Robinson Humphrey in the Mergers and Acquisitions group. Before SunTrust, John also worked in the corporate finance group at Porsche Cars North America. Through these experiences, John sharpened the analytical framework he uses daily at Riverstone Advisors.

John decided to leave the investment banking and corporate finance worlds to join Riverstone Advisors because he enjoys helping people and working in a role that allows him to stay true to his values.

He is currently a board member of the Georgia Tech Alumni Association Board of Trustees and on the Atlanta Juvenile Diabetes Research Foundation (JDRF) Board of Directors.

When John is not working, he enjoys spending time with his family, fly fishing, and participating in triathlons.

Giving Back

Juvenile Diabetes Research Foundation

The Juvenile Diabetes Research Foundation is the leading global organization funding type 1 diabetes (T1D) research. JDRF’s goal is to progressively remove the impact of T1D from people’s lives and eradicate the disease.

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The Kyle Pease Foundation

The Kyle Pease Foundation improves the lives of people with disabilities through sports. Programs may include scholarship opportunities, purchasing of medical equipment or adaptive sports equipment for others or contributing to other organizations that provide similar assistance to disabled persons as well as participating in educational campaigns to create awareness about Cerebral Palsy and other disabilities.

The Kyle Pease Foundation will provide these services directly to individuals, as well as to partner with other existing non-profit organizations, to achieve these goals. Direct benefits will be limited to persons with disabilities who need adaptive sports equipment, mobility devices or medical care.

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Allison Rickerson

Client Services and Operations Associate

Allison joined Riverstone at the end of 2018 and serves as the Client Services and Operations Associate. Prior to working for Riverstone, Allison graduated from The University of Texas of the Permian Basin and was a classroom educator for the Texas school system. She left the classroom to raise her kids and worked as an office manager for a family-owned business. She brings organizational skills and keen attention to detail to the Riverstone Advisors team. Allison has her Series 65 license.

Allison volunteers to teach a women’s Bible Study outside work and mentors college and young adults through her church. Allison is married with 3 kids who keep her busy with their many sports and activities. She enjoys reading, being crafty, and loves to travel with her family. On her bucket list is to visit all the Major League Baseball parks.

Matthew Williams

Director of Financial Planning

Matthew serves Riverstone as the Director of Financial Planning, building on the firm’s investment experience to help clients build long-term wealth through a holistic approach to financial wellbeing. He focuses on breaking down the complexities of various savings programs, investment vehicles, and retirement plans to develop a personalized strategy for each client.

Matthew is passionate about adapting traditional financial advice to meet the unique needs of one’s chosen family, especially within the LGBTQ+ community. Whether that includes family planning, nonprofit giving, a nephew’s college tuition, or an early retirement, he enjoys developing a relationship with clients to build and maintain a plan to achieve their goals.

After graduating from Georgia Tech in 2007, Matthew worked in various strategy, development, and analytics roles at Google, Gap Inc, and Delta Air Lines. These experiences fostered a healthy disregard for the impossible and a belief that there are always positive outcomes waiting to be discovered. Applying this mantra to financial planning, he enjoys working through complex issues to help clients reach their goals.

Beyond financial planning, Matthew is an avid snowboarder and weightlifter. He and his husband have two dogs, Hendrick the Boxer and Harry the Labradoodle. Matthew serves on the board for Up3, and he and his husband are avid supporters of Atlanta’s local NPR station, WABE.

Giving Back


Up3 is an Atlanta-based non-profit helping foster youth pursue passion-based skills development and education after aging out of the foster system. Up3 exists to highlight and help cultivate foster teens’ individual areas of passion to expose them to new experiences, build confidence, teach critical life skills and expand vocational opportunities.

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As the NPR and PBS affiliate for the metro-Atlanta area, WABE provides national content and award-winning journalism, radio shows, podcasts and television programs. WABE is 100% independent, 100% nonprofit and 100% committed to amplifying diverse voices in Atlanta through their mission to inform, inspire, reflect and empower.

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You don’t want a financial advisor to tell you what you want to hear.

You’re looking to make money, not just sit on it.