Texas License: C-11847 | Louisiana License: 7311-011910-LA | Alabama License: 395

Texas License: C-11847 | Louisiana License: 7311-011910-LA | Alabama License: 395


Why select Gillespie Security & Investigations? Why me? In my previous career as Special Agent for the Air Force Office of Special Investigations (AFOSI), I was blessed to have had the opportunity to develop outstanding skills at conducting a broad range of investigations and security services -- ranging from homicide investigations and personal threat assessment to counterespionage. After retirement from the Air Force I served as the Director of Forensic Science for the Austin Police Department. In later years I carried my passion for forensic science and teaching to St. Edwards University where I was responsible for developing their forensic science undergraduate degree program. I also contributed seven years as a board member (last two as President) for the Texas Association of Licensed Investigators (TALI), one of the largest P.I. Associations in the nation. I mention all of this not to blow my own horn, but to emphasize that I have the tools, background, experience, training and passion to provide you with the most professional safety, security and investigative services.

We live in dangerous times, from work-related security issues to everyday threats affecting family members’ safety. Many of us also face domestic disputes or legal threats that endanger our future happiness. That’s why I founded Gillespie Investigations. I’m here to give you the vital information and resources you need for a safer, more secure life.

Give Mark a call today at 512-680-5851 or email at This email address is being protected from spambots. You need JavaScript enabled to view it..  

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605 South Bell Blvd, Suite 104
Cedar Park, TX 78613
(512) 680-5851