The launch of portable Internet, alongside mobile Internet technology and cellular technology, is a new milestone, converging wireless with wired technology. Along with these new technologies, a new telecommunication service has been introduced and has received much attention from the Korean public. This is the Digital Multimedia Broadcasting (DMB) service. DMB is a digital multimedia service combining telecommunications with broadcasting technologies. DMB enables users to watch various multimedia contents on their phone screens while they are on the move. Since DMB services in Korea are the first in the world, the Korean Government has much interest in DMB services. However, the repeated failures in establishing a regulatory framework for DMB and ill-defined roles of players in the DMB industry interfere the diffusion of DMB in the Korean market. As the convergence of broadcasting and telecommunications makes progress, proper modifications of existing regulatory frameworks should be made in order to guarantee success of DMB service in Korea. This chapter reviews DMB technology, its business model, its market structure, and its policy. In particular, it explores business opportunities around DMB services and identifies major issues that must be solved to launch DMB services successfully.