Fixed-mobile convergence services can be defined as the combination of previously separate fixed and mobile services, and networks and commercial practices. Examples of fixed-mobile convergence services include single voicemail box, single number and unified messaging across fixed and mobile networks. Recently as more voice is transferred to mobile networks, convergence services between fixed and mobile become more important. In Korea convergence services are only starting to become established, and are likely to become an important part of any operator's offering. In this paper, I search the different levels of fixed-mobile convergence services and the trends and regulations for fixed-mobile convergence services in major countries. And at the same time I also try to find a new direction of future regulatory principles related to fixed-mobile convergence services.