Project 25 systems have subscriber units and fixed equipment which comprises the infrastructure. There are a number of external interfaces to the system, and specifically this document addresses the Network Management Interface En. The objective of the Network Management Interface is to ensure a standardized interface between the End System Network Management Center (NMC) and an Operations and Maintenance Center - Radio Frequency (OMC-RF) located within a Radio Frequency Sub-system, so that an NMC can manage Radio Frequency Subsystems (RFSS) sourced from other vendors. The network management interfaces between the fixed RFSS equipment and the OMC-RF could be standardized, but are beyond the scope of the Project 25 standard. The Network Management Interface is part of an intended suite of standards necessary for interoperability. A general overview of the Project 25 standard exists in the Project 25 System and Standards Definition [1]. The reader should have familiarity with this document. The following three sections will identify the proposed standards for: 1) the Network Management hierarchy, 2) the transportation medium of Network management information between an NMC and an OMC-RF, and 3) the definition of the Project 25 system management functional areas.