The results of the data analysis document and empirically confirm the presence of several distinctive patterns in tribal policing in the United States. The first notable pattern is the recent growth in tribal policing agencies. The second notable pattern is the continuing influence of Public Law 280 in limiting development of tribal self-government and self-policing. The third pattern revealed in the analysis is that tribal police departments seem to look and operate pretty much like police departments do anywhere in communities of comparable size and geographic location. The results identified provide an empirical reference point for assessing future changes and developments in this mostly undocumented form of policing. Despite half a century of research and data collection on thousands of police agencies throughout the United States, there is only a sketchy, incomplete, impressionistic picture of how policing occurs within the communities of its original inhabitants, i.e. American Indian tribes. This study provides a more comprehensive empirical picture of Indian Country police agencies in the United States using reliable data available at the onset of the 21st century. It provides a summary of the basic organizational features of tribal police departments in the United States, to see how these features may differ across tribal communities, and to examine how tribal police compare or contrast with the non-Indian police agencies in the United States more generally. Figure, tables, notes and references