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.

Martin Hubert brings a wealth of state government experience to the clients of Cornerstone Government Affairs. From his early career as chief counsel to the Senate Natural Resources Committee to his gubernatorial appointment as a commissioner of the Texas Commission on Environmental Quality to his eight years as the deputy comptroller of Texas, Hubert has managed thousands of employees and millions of taxpayer dollars under both Democrat and Republican administrations.

Martin was the 2008 recipient of TSABAA's Administrator of the Year Award. Presented annually, this prestigious award was established to formally recognize state employees who have demonstrated outstanding leadership skills and who have made significant contributions to state agency business administration.

As the final general counsel to legendary Lt. Governor Bob Bullock, Martin learned the mastery of government relations from some of the most influential leaders in Texas history. His knowledge of agriculture stems from generations of the Hubert family's cow/calf and farming operations in South Texas and serving as the Texas Deputy Commissioner of Agriculture for eight years. Martin offers a unique combination of legal, natural resources, tax policy and state government procedural expertise.

Hubert is a graduate of the Georgetown University Law Center and St. Mary's School of Law. He was Brigade Executive Officer in the Corps of Cadets at Texas A&M University, where he was a member of the Ross Volunteers Honor Guard and the Singing Cadets. He successfully completed Army Ranger School and served in the U.S. Army Reserves. He is a marathon runner and coaches his son's little league teams.

Hubert is a second tenor and helps raise money for Legal Aid through the Travis County Bar Association's "Bar and Grill" fundraisers. He and his wife Celeste live in a historic home in Austin, where they are involved with the Austin Symphony, St. Theresa's Catholic Church and School, and the happily busy lives of their children Belle and Patrick.

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.

Tony Essalih joined Cornerstone in 2011 as a co-lead of the firm's flagship Texas office in Houston. He spent 12 years on Capitol Hill and came to Cornerstone from the office of Congressman John Culberson (R-Houston). Tony worked for Congressman Culberson for 10 years, the last five as his chief of staff. Prior to becoming chief of staff, Tony served in a variety of capacities including legislative assistant, legislative director, communications director, and deputy chief of staff. He spent eight years in Washington, D.C. before relocating to Houston in 2007.

As chief of staff, Tony was responsible for guiding the day-to-day operations of the Congressman's Washington and Houston offices, and oversaw a 15-member staff under a fixed budget. Outside of the office, he served as the principal liaison to the Congressman's campaign committee and provided strategic counsel and advice related to his re-election efforts. Tony's areas of policy expertise include transportation, energy, budget and appropriations. Tony also led outreach efforts and served as an emissary on behalf of the Congressman with state lawmakers in Austin and local elected officials in Houston.

Prior to Culberson's election in 2001, Tony worked as a legislative assistant for Congressman Culberson's predecessor, former House Ways and Means Committee Chairman Bill Archer. Tony's began his tenure on Capitol Hill with former House Natural Resources Committee Chairman Doc Hastings.

Tony has advised and assisted numerous local, state, and federal campaigns. He serves on the board of the National InterFaith Foundation, the Advisory Board for the Houston Technology Center, spent two years on the Board of the Spring Branch Medical Center and was a member of Houston Mayor Annise Parker's transition team in 2010.

Tony was born and raised in Fredericksburg, VA and received his B.A. in Political Science from Mary Washington College. He was a member of Mary Washington's NCAA semifinalist men's soccer team. He lives in Houston and has two angelic daughters, Grace and Libby.

Anne Mazuca brings over a decade of legislative experience working at the Texas Capitol, most recently serving six years as Chief of Staff to State Representative R.D. ‘Bobby' Guerra.

During her time working in the Texas legislature, she has worked for Members from Dallas, Galveston and South Texas, allowing her the opportunity to build relationships with local elected officials, community leaders and stakeholders from across the state while working on a wide range of policy areas. Prior to being named chief of staff, she served as a legislative director and legislative aide where she was the primary staff lead for the House Appropriations Committee Article II and Article III focusing on healthcare and education funding, the Public Health Committee, Energy Resources, Business & Industry, Ways & Means and Insurance committees.

In her capacity as chief of staff, Anne was responsible for guiding the day-to-day operations of the Capitol and McAllen offices. Outside of the office, she provided support for her Member's re-election campaign where she provided feedback on messaging, managed all Texas Ethics Commission and campaign finance filings and offered general advice and assistance related to his campaign.

An Austin native, Anne has close ties to the city in which she still resides.

Rachel Cone joins Southern Strategy Group after more than a decade of service in the highest levels of local and state governments. Rachel served as the Interim Secretary for the Florida Department of Transportation (FDOT), where she successfully shepherded the department's policy agenda and $11 billion budget across the finish line of the 2017 legislative session.

During her time at FDOT she also served as the Assistant Secretary for Finance and Administration, overseeing the offices of work program and budget, finance, procurement, technology, human resources, performance management and other administrative functions. She managed three of the largest transportation work programs in state history and represented the department in front of the U.S. Department of Transportation, the U.S. Treasury, Fitch and Moody's rating agencies.

Rachel also directed changes to how the department finances the work program, and successfully advocated for statutory changes that resulted in a new financing vehicle for the department. This allows the department to fund additional, major transportation projects at a lower cost. She also oversaw the reorganization of the department's technology offices, which resulted in a culture shift for the department in how it prioritizes, spends and manages transportation-specific and traditional technologies.

In 2012, Governor Rick Scott appointed Rachel to serve as his Deputy Chief of Staff, where she was responsible for advising him on statewide issues, appointments to boards and commissions and providing guidance and direction to 14 state and quasi-governmental agencies on operational and management issues, including policy, budget, communication, legislative strategy and agency priorities. Those agencies were the Departments of Business and Professional Regulation, Citrus, Emergency Management, Economic Opportunity, Environmental Protection (and Water Management Districts) and Transportation. Also included under her purview were Florida Wildlife Commission, Space Florida, Visit Florida, Volunteer Florida and CareerSource Florida.

Rachel previously served as the External Affairs Director for the Florida Department of Environmental Protection where she directed planning and statewide communications strategies for the department, and coordinated communications efforts with Florida's five water management districts. This included topics such as renewed water management district oversight, various departmental restructuring, the health of Florida's springs, Governor Scott's Everglades Restoration Strategies plan and Florida's ongoing recovery after the 2010 Deepwater Horizon oil spill.

Prior to her family's move to Tallahassee, Rachel served on the executive leadership team in the Mayor John Peyton administration in Jacksonville. Rachel began her career as a military reporter at the Florida Times-Union.

Rachel is a proud graduate of Auburn University. She and her family are active members of Trinity United Methodist Church, and Rachel serves as a member of the Board of Trustees at Holy Comforter Episcopal School in Tallahassee.

Laura Alexander joined Cornerstone in October of 2025 as a Principal for our Texas office, and is based in Houston. She supports client teams in a variety of issue areas.

Prior to Cornerstone, Laura served as Vice President of Public Policy at the Greater Houston Partnership. In this role, she led advocacy on water infrastructure, workforce development and public school funding; managed member fly-ins and delivered key outcomes during the 89th Texas Legislative Session, including local appropriations for the City of Houston, extension of research & development franchise tax credits and a constitutional dedication of funds for water projects.

Laura previously practiced public finance law, holding roles with a number of firms in Louisiana focusing on environment, energy, tourism, housing and elections. She also served as Executive Director of the Louisiana Institute for Children in Families, where she advanced foster care and adoption reforms and launched the Louisiana Foster Youth Intern Program to prepare former foster youth to testify before the Legislature.

Laura holds a Juris Doctor from Loyola University New Orleans College of Law and a BA in Mass Communication from Louisiana State University.

Craig Holzheauser brings to Cornerstone years of involvement in Texas state and local politics. The son of a state representative, Craig went to work in the private sector after college before beginning a political career at the state capitol in 2012.

Working as a legislative consultant, managing the campaigns of House and Senate members, and serving as legislative director and then committee director of the House Committee on Public Health in his first year of employment, Craig is goal oriented and proven himself to be a quick study. Craig has a keen political intuition and a knack for developing the type of relationships that matter in campaigns, service of an elected official, or success for his clients.

A native of Victoria, Texas, Craig holds a Bachelor of Science in Construction Science from Texas A&M University.