Maintenance of appropriate fluxes of monovalent cation is a requirement for growth and survival. In the budding yeast Saccharomyces cerevisiae an electrochemical gradient of H(+) is fundamental for the uptake of diverse cations, such as K(+), and of many other nutrients. In spite of early work suggesting that alterations in monovalent cation fluxes impact on the uptake and utilization of nutrients, such as phosphate anions, only recently this important aspect of the yeast physiology has been addressed and characterized in some detail. This chapter provides a historical background and summarizes the latest findings.