Ross Giesinger brings over a decade of legislative experience at the Texas Capitol to the Cornerstone team, having served for six legislative sessions in both the Texas House and Senate.

Most recently, Ross worked as a policy advisor to Dade Phelan, Speaker of the Texas House, of Representatives, during the 87th Regular Session, where he assisted with the passage of over 80 pieces of legislation. Additionally, Ross drafted and managed several bills filed in response to Winter Storm Uri, including SB 3, one of the most comprehensive energy reforms in Texas in the last 20 years.

Prior to his time in the House, Ross spent several years working as general counsel and legislative director for Sen. Lois Kolkhorst (R-TX) and as the director of the Senate Committee on Health and Human Services. While at the Senate, Ross assisted with the passage of nearly 300 bills and worked to obtain funds for a variety of initiatives, including legislation that secured permanent funding for Texas State Parks.

Ross began his career at the legislature in 2010 as a drafting attorney for the Texas Legislative Council. During his time with the state, he has drafted thousands of pieces of legislation, allowing him to develop expertise in a wide variety of subject areas, including energy, healthcare, water, land use and development, transportation, insurance, labor, agriculture, wildlife, taxation, and state budgeting.

Ross is a graduate of the University of Texas at Austin and Southern Methodist University's Dedman School of Law. He is a member of the Austin Young Lawyers Association and was recently elected to serve on the Council of the Texas State Bar's Legislative and Campaign Law Section. Ross also serves as a Steward of the Wild for the Texas Parks and Wildlife Department and has been active in the Austin Ballet Guild, the Trail Foundation, and CCA. He and his wife Courtney live in Austin with their young son Henry.

Matthew Garcia joined Cornerstone in December of 2024, expanding the firm's Texas footprint to Dallas. A seasoned government and public affairs executive with over two decades experience in the Dallas Region, Matt brings a wealth of experience in policy, advocacy and stakeholder engagement. He joins Cornerstone from the Dallas Regional Chamber, where he served as Senior Vice President of Public Policy and Advocacy. In this role, he spearheaded the organization's public policy strategy, while remaining closely engaged with legislators, key stakeholders and C-level executives across the Dallas Region for one of the largest Chambers of Commerce in Texas.

Prior to his time at Dallas Regional Chamber, Matt worked as the Director of External Affairs for Leon Capital Group where he developed the firm's public affairs strategies across their multiple business lines.

Previously, Matt served in the United States House of Representatives, first as District Director (2010-2013) and then as Chief of Staff-Texas (2013-2018), managing Rep. Pete Sessions' (R-TX) office and serving as a key advisor on energy, transportation and general business issues for Texas. Notably, Matt served as the North Texas congressional point of contact working with area city officials, the North Texas Municipal Water District (NTMWD) and the Army Corps of Engineers to bring online Bois d'Arc Lake, the newest major reservoir in Texas in over 30 years. Matt also worked alongside emergency response teams at the city, county and state levels during the 2014 Ebola crisis in Dallas to deliver accurate and timely public communication while leading information coordination with federal agencies, including the National Institute of Health and the Department of Health and Human Services.

He earned his bachelor's degree in finance from the McCombs School of Business at the University of Texas at Austin. Garcia currently serves as Director of the Texas Association of Business, The Dallas Zoo and the Texas Lyceum, and member of the following organizations: McCombs School of Business BBA Advisory Board, Simmons Cancer Center Community Advisory Board, Reading Partners North Texas, the State Fair of Texas Chairman's Task Force, the YMCA of Metropolitan Dallas Brand Advancement Committee and the SMU Corporate Communications and Public Affairs Advisory Board.

Zoe Halfmann joined Cornerstone as a Principal in our Dallas office in September 2025.

Prior to Cornerstone, she was Chief of Staff to Dallas City Councilmember Paula Blackmon. In this role, she advised on key policy initiatives related to preemption, mental health, , fentanyl and funding for district projects. She oversaw the Councilmember's agenda, collaborated directly with city executive staff and fellow councilmembers, managed internal operations and coordinated media and communications strategy.

Prior to that, Zoe served as Vice President of Public Policy at the Dallas Regional Chamber, where she managed local government relations and led the organization's work in critical areas including infrastructure, healthcare and water policy. She also helped lead the formation of the Good for Texans PAC, provided on the ground support during the 88th Session of the Texas Legislature, and revitalized the organization's Infrastructure Task Force to advance regional priorities. Zoe also organized high-profile events including coordinating state and federal fly-ins, hosting the Texas Governor and the Speaker of the House, and planning roundtables with local and national stakeholders.

In addition, Zoe has held various roles within the City of Dallas including Legislative Manager, Council Liaison and Policy Advisor and Legislative Coordinator.

She holds a Master's in Public Administration from the University of North Texas, where she was a Hatton Sumners Scholar. She also has a Bachelor of Arts in Political Science from the University of Arkansas.