The advent of cheaper and more powerful devices with the ability to play, create, and transmit video content has led to a dramatic increase in the multimedia content distribution on both wireline and wireless networks. Also, the reduction of cost of digital video cameras along with the development of user-generated video sites (e.g., iTunes™, YouTube™) stimulated a new user-generated video content sector and made unprecedented demands for high-quality and low-delay video communication. The Region-of-Interest (ROI) is a desirable feature in many future scalable video coding applications, such as mobile device applications, which have to be adapted to be displayed on a relatively small screen; thus, a mobile device user may wish to extract and track only a predefined ROI within the displayed video. At the same time, other users having a larger mobile device screen may wish to extract other ROIs to receive higher video stream resolution. Therefore, to fulfill these requirements, it would be beneficial to simultaneously transmit or store a video stream in a variety of ROIs, as well to enable efficiently tracking of the predefined Region-of-Interest. This chapter presents recent advances in Region-of-Interest video and image processing techniques for multimedia applications, while making a special emphasis on a scalable extension of the H.264/AVC standard. The detailed observations and conclusions, which are presented in this chapter, are supported by authors’ personal experience in this field, thereby presenting a variety of experimental results.