Mario Atencio is Háshtł'íishnii; born for Tódichíinii; Táneezháanii are his cheiis and Tłaasch'í' are his nálís.  He has been involved in oil and gas development issues facing the Diné communities of the far eastern Diné Nation.  Mario became involved with Diné CARE by starting the work around the Colorado River water rights struggle that the Diné Nation is still facing.  He joined Diné CARE in 2017 as board member at large.