Telling the story of the Sonora region through primary documents has often vexed researchers because many of these documents are held in three separate institutions. Recently, these three institutions teamed up to create a digital archive which contains key documents from these collections. The project was supported by a grant to the University of Arizona Library from the Institute of Museum and Library Services. The documents cover a wide range of themes, including mining, land grants, border crime, and anti-Chinese movements. Visitors can search the entire collection, or they may wish to begin by browsing through the collections. The collection documents are organized by contributing institution, and visitors will find everything from Arizona territorial correspondence to the papers of Jos" Maria Arana. Arana was a well-known businessman in Magdalena, Sonora, and he also happened to be the leader of several anti-Chinese campaigns. Overall, the collection is quite fascinating, and it's a great example of the fine results that can be obtained through collaborative partnerships.