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In the late 1800s, there were believed to be 1,500 desert bighorn (Ovis canadensis mexicana) roaming throughout 16 mountain ranges in the Trans-Pecos region of Texas. However, Texas lost all of its native desert bighorn during the mid-1900s, as well in Mexico, the states of Chihuahua, Coahuila, and Nuevo Leon lost their desert bighorn. Causes are believed to be associated with overgrazing of domestic sheep, diseases, predation, fragmentation of land, and overhunting. Beginning in 1959, translocation efforts initiated in Texas to restore desert bighorn to their historic habitats. Since 2010 to 2015, 172 bighorn (63 rams and 109 ewes), of 246 captured and released, have been fitted with GPS radio collars for research purposes. Over the last 4 years, we have investigated 53 bighorn mortalities in the Big Bend area and Mexico. During the 3-year study at Big Bend Ranch State Park (BBRSP), 54 collars were successfully recovered. These collars have produced over 100,000 GPS points for our analysis. Twenty one (39%) of the 54 collared bighorn were documented crossing into Mexico and 18 (33%) ventured onto private lands outside of BBRSP. The states of Chihuahua and Coahuila initiated restoration efforts in 2000 in breeding areas where they have successfully increased their populations. As of June 2012, there were 4 captive breeding desert bighorn sheep herds in Chihuahua. And there it is reported to have been 281 desert bighorn sheep at the time in that state. Our restoration efforts are on a larger scale than previously thought with desert bighorn crossing international borders. The knowledge gained from our studies will continue bettering our understanding of bighorn restoration and conservation efforts in Texas, and in the Chihuahuan Desert. Without collaborative conservation (public, private, and international), the desert bighorn sheep restoration program would not be as successful as it is today.