The paper analyzes the prospects of the emergence of alternative units of account due to technological and institutional innovation in the payments system, and as a consequence the appearance of electronic money. Due to network effects and switching costs, both the issuers and the users of electronic money face strong incentives to adhere to the dominant unit of account. The most likely institutional structure of new electronic payments systems to emerge implies the redeemability of electronic money on requirement and its denomination in the dominant unit of account