Collaboration with indigenous peoples has been a hallmark of ethnology since the mid-19th century, and throughout the 20^th century numerous anthropologists acknowledged indigenous and local cultural specialists as co-producers of project results and knowledge. In recent decades, converging and co-mingling influences from inside and outside of anthropology - including action anthropology, community heritage studies, and passage of the Native American Graves, Protection and Repatriation Act (NAGPRA) - have led increasingly to wide-ranging kinds of consultations and partnered collaborative and participatory projects being conducted within or from museums.