We present an analysis and discussion of the "tanda," a multiperson pooled credit and savings scheme (a rotating credit association or RCA), as described by two informants from Mexican immigrant communities in California. In the tanda, participants contribute regularly to a common fund which is distributed to participants on a rotating basis. We analyze the tanda at multiple levels (as a mathematical, cultural, and distributed practice) and identify points of intersection and conflict. Contrary to many formal or school-based conceptions of mathematics, mathematical work in the context of the tanda is in service of, and intimately tied up with, cultural goals and values. Likewise, cultural means and mathematics are employed to personal ends. We argue that the tanda should be of enduring interest, particularly among educators interested in bringing more authentic, culturally-relevant mathematics into classroom settings, because it so clearly illustrates how mathematical and cultural processes can interact in the context of personal goals, and provides a potentially valuable template for engaging, consequential, and successful mathematics. (Contains 1 table and 4 footnotes.)