The Agua Caliente are a band of Cahuilla who have lived in the Coachella Valley of Southern California for at least 2,000 years. With the establishment of the reservation in 1876, the Agua Caliente went from the traditional hunting and gathering lifestyle to farming and ranching. The modern reservation of today is comprised of three resort cities (Palm Springs, Rancho Mirage, and Cathedral City) and one county: Riverside. The tribal members enrolled in the reservation number about 350. The Band is the largest single landowner in Palm Springs. The reservation boundary is like that of a checkerboard involving one-mile square sections with adjacent odd numbered sections being granted to the Southern Pacific Railroad. The approximately 32,000 acres fans out across three desert townships and over the sheer slopes of the San Jacinto Mountains. Within each reservation section there may be a mix of individual Indian allotments, tribal tracts, and parcels that have been sold into fee simple ownership. Many of the individual allotments have been developed under large residential resort leases. Because of the tribe's valuable land interests and the complicated jurisdictional issues posed by the cities, the County, individual allotments, and leasing, GIS has become an important tool in managing, regulating, developing, and protecting tribal resources. The tribe recognized the importance of GIS and started using the technology in 1990. The GIS Department is now an integral part of the Tribal Planning Office. This presentation will highlight the significant GIS accomplishments within the past year.