This paper focuses on how regulators can effectively safeguard customer funds when a nonbank issues mobile money. In countries where this is permitted, regulators and nonbank mobile money issuers have taken a number of steps to mitigate the risk that the latter will be unable to reimburse their customers. The purpose of this paper is to help regulators and mobile money issuers better understand how to effectively safeguard customer funds against risk of loss due to (1) imprudent investment of customer funds, (2) insolvency of the mobile money issuer or trustee/fiduciary, or (3) insolvency of the bank holding the customer funds.