HTML is a major part of the new media landscape, and it offers many benefits for some types of ITV applications. This chapter discusses how we can develop HTML applications in MHP and OCAP. As well as looking at the new features HTML applications can use, we will look at how an HTML user agent fits in to the rest of the system and how it interacts with other applications that may be running. We also discuss how broadcasters are using HTML today, and how this differs from the MHP and OCAP vision of how it should be used.