Chagas disease, also known as American trypanosomiasis, is caused by the hemoflagellate protozoan Trypanosoma cruzi which is transmitted by blood-sucking triatomine bugs (Hemiptera: Reduviidae; Triatominae). The disease is endemic to south Texas, but exists almost exclusively as a zoonosis. Chagas disease has proven to be a serious public health threat to military working dogs. In 2007, seroprevalence of Chagas disease in military working dogs in San Antonio, Texas, reached 8%. A faunal survey was conducted at 3 San Antonio area military installations (Camp Bullis, Fort Sam Houston, and Lackland Air Force Base). A total of 140 triatomines representing 4 species (Triatoma gerstaeckeri, T. sanguisuga, T. lectularia, and T. indictiva) were collected. Trypanosoma cruzi infected bugs were only collected at Lackland Air Force Base, where the overall infection rate was 16%. The wood excavation technique developed during this study collected all life stages. Only 2 life stages (adult and 5th instar) were positive for T. cruzi.