The Tamástslikt Cultural Institute is a museum and research institute located on the Umatilla Indian Reservation near Pendleton in eastern Oregon. The institute is dedicated to the culture of the Nez Perce, Walla Walla, and Cayuse tribes of Native Americans. The main permanent exhibition of the museum provides a history of the culture of three tribes, and of the reservation itself. The museum also has a second hall for temporary exhibitions of specific types of Native American art, craftwork, history, and folklore related to the tribes. The name Tamástlikt means "interpreter" in the language of the three tribes, which are closely related.