Local Number Portability (LNP), an Intelligent Network (IN) service, provides the ability to retain existing telephone numbers when switching from one telecommunications carrier to another, from one region to another, or from one service to another. Local Number Portability (LNP), an Intelligent Network (IN) service, provides the ability to retain existing telephone numbers when switching from one telecommunications carrier to another, from one region to another, or from one service to another. LNP is a key service for increasing competition in the local telephone marketplace. Many countries are now establishing detailed rules for ensuring competition between network operators. Because many major carriers will deploy their own LNP databases, a single access point must be provided to effectively manage and distribute updates to the common regional LNP database. This is called Number Portability Administration Center (NPAC). Recently, CORBA is being accepted as one of the key technologies for developing distributed application systems. To use CORBA for managing IN services, several standard organizations are working towards the integration of IN, TMN and CORBA. In this paper, we present our work on applying the TMN and CORBA technology for the service management of LNP. We first propose a CORBA-based LNP service management system architecture, We then present the design and implementation of a LNP service management system using CORBA.