New technological developments have continued to generate growth opportunities in the communication service sector. They are creating new markets and services but also new challenges to policy and regulation. The chapter examines key developments in competition and regulation in OECD markets during this period of change. It explains how local loop unbundling and broadband competition in general have changed the competitive landscape in many OECD countries. It also covers issues of state ownership of telecommunication firms and restrictions on foreign investment, the regulatory treatment of VoIP and fixed-to-mobile interconnection. Finally, it examines the increasing importance of communication in overall household expenditures in the OECD area.