Operational

Gary Hall

With over 30 years of experience, Gary Hall holds extensive knowledge and expertise in commercial, sports, and entertainment construction. A valued industry leader, Gary excels at bringing teams together on large, complex projects and doing so with integrity and respect. He currently represents Project Control and PC Sports as a Senior Vice President and is responsible for overseeing the Central Texas office. Gary received his Construction Science degree from Texas A&M University and was recently honored by his alma mater as an Outstanding Alumnus by the College of Architecture.

Charles 'Dude' Hall

Dude has over 30 years of professional experience in the environmental field in both the government and private sector. Dude led Timber Creek Environmental (TCE), which was acquired by Raba Kistner in 2018. The firm was based in Conroe with additional offices in San Antonio and Dallas. Dude's leadership at TCE focused on supporting the manufacturing/industrial sector with major national clients. In Dude's current role, he is supporting the expansion of our environmental services in the Houston, Dallas-Fort Worth and San Antonio marketplaces, as well as across other regions and nationally for large clients.

Jeff L. Haberstroh

Jeff Haberstroh has accumulated over 30 years of experience as a Project Manager in the San Antonio region. Jeff holds extensive experience managing bond programs and construction projects for municipalities and school districts, including most recently leading the Project Control team on the Henry B. Gonzalez Convention Center and Alamodome expansion and renovations projects for the City of San Antonio. As a Program/Project Manager, he has managed all project phases from concept, contract negotiations and pre-construction services to complete bond oversight and project operations, to budget and schedule management.

Isabel Gongora, CPA

Isabel Gongora is a dynamic and results-oriented leader with more than 20 years of expertise in accounting, financial reporting, and operational management. As a licensed CPA and holder of a Master’s degree in Accounting from the University of the Incarnate Word, she brings a deep understanding of GAAP financial reporting, financial analysis, and internal controls. Her forward-thinking approach has consistently driven significant improvements in efficiency, accuracy, and regulatory, establishing her as a trusted advisor and a driving force for organizational growth.
Throughout her career, she has worked across diverse business units, entities, and divisions—partnering with senior leadership to align financial operations with strategic goals. Known for her integrity, collaborative spirit, and strong work ethic, she leads and mentors high-performing teams while fostering a culture of trust and accountability. Her ability to distill complex financial concepts into clear, actionable insights makes her a valued advisor and strategic partner.
Tech-savvy and future-focused, Isabel embraces emerging technologies and artificial intelligence to streamline processes and elevate data quality. Whether refining procedures, guiding audit readiness, or developing talent, she approaches every challenge with clarity, precision, and a commitment to excellence.

Troy Gardner, PE

Troy Gardner has over 15 years of experience in materials testing, inspection, and project management on major transportation, government, industrial, and commercial projects. He has held key roles on several large-scale UDOT projects, including serving as Quality Construction Manager on the West Davis Corridor, Quality Manager on UDOT’s first $525M Progressive Design-Build project, and Lead Engineer on the $415M Technology Corridor I-15 widening. His expertise includes leading inspection and testing teams, managing quality programs, and coordinating with contractors, UDOT, and stakeholders on complex, high-value infrastructure projects.

Steven W. Funderburg, PE

Steven has more than 40 years of professional experience, including 25 years with Raba Kistner. While he is an engineer, he is educated in both science and engineering and has professional experience in both disciplines. During his career, he has successfully managed a wide variety of projects that have required contributions from scientists, engineers, and professionals from non-scientific fields.

Mike Frisbie, PE

Mike serves as Raba Kistner’s strategic growth leader in the San Antonio and Austin marketplaces and oversee the regional growth of Raba Kistner’s four business lines across public and private sectors — engineering consulting, infrastructure, environmental, and project management.

He has demonstrated executive leadership performance in planning, directing and overseeing large-scale engineering, infrastructure, water, wastewater, streets, storm water, and traffic management operations, with accountability for up to 1075 employees while managing large Annual Operating Budgets and Capital Improvement Programs.

Susan Filyk, MBA

Susan leads Raba Kistner’s marketing team and is responsible for the firm’s branding, public relations and corporate communications. Joining Raba Kistner in 2018, Susan brings more than 25 years of experience in communications and marketing in the corporate and non-profit sectors, focusing on branding strategy, creative management, product development, content creation, and investor relations.

Chris Evans

Chris Evans is a seasoned technology executive with over 30 years of experience leading innovation in software development and systems integration. As VP/CTO at Raba Kistner, Inc., he drives enterprise-scale solutions that align technology with business strategy. Chris is known for his ability to translate complex needs into scalable architectures and for building and motivating high-performing teams. His background spans startups to established firms, with deep expertise in SaaS, cloud computing, agile methodologies, and application development. A hands-on leader and strategic thinker, Chris blends technical depth with executive vision to deliver impactful results.

Anthony Calabrese, PMP, LEED AP

With over $1 billion in projects managed to total more than three million square feet, Anthony Calabrese brings expertise and care to all projects. Anthony’s collaborative, solutions-based management style places importance on active listening with Owners and project teams. He carries this approach from project inception through Owner operation, affording client’s projects the highest level of valuable scope within budget, and a facility maintainable by the Owner. Anthony achieved a Bachelor’s from Devry University and a Master’s from Keller University in between serving three tours in Iraq as a US Navy Seabee.

Ralph Browne, PE

Ralph brings decades of experience in preparing and managing the technical aspects of the project as well as coordinating with utilities and public agencies to avoid construction delays and successfully deliver on projects. Ralph has served over 26 years within several districts of TxDOT including Austin, El Paso and Fort Worth and 11 years as a consultant. His career has also included specialized service for the analysis of construction claims utilizing this skill in the administration of construction projects allowing him to protect clients while progressing projects.