As far as payment systems are concerned, central bank action consists in setting oversight standards to guarantee the regular functioning of these systems and, in many cases, in the direct operation of wholesale and retail clearing and settlement systems. Standards also have the objective of ensuring equal treatment between the systems operated by central banks and those operated by private-sector bodies and to minimize possible conflicts of interest between the operational and the oversight activities of the central banks themselves. Oversight bears on large-value and retail systems whose size and/or risk profiles make them important to the regular functioning of the payment system and to the maintenance of confidence in the currency and in non-cash payment instruments.