This memo defines a portion of the Management Information Base (MIB) for devices implementing the Network Address Translator (NAT) function. The new MIB module defined in this document, NATV2-MIB, is intended to replace module NAT-MIB (RFC 4008). NATV2-MIB is not backwards compatible with NAT-MIB, for reasons given in the text of this document. A companion document deprecates all objects in NAT- MIB. NATV2-MIB can be used for monitoring of NAT instances on a device capable of NAT function. Compliance levels are defined for three application scenarios: basic NAT, pooled NAT, and carrier-grade NAT (CGN).