In this chapter, we provide an overview of the technology that has finally been standardized in MPEG-4. Let s start with a description of the underlying trends that have initiated and shaped the technical content of the standard. These trends have induced a number of new application scenarios and service proposals dictating technical requirements that were subsequently transformed into an overall technical framework for MPEG-4. We will discuss the resulting overall architecture on a conceptual level to highlight how it is fundamentally different from existing coding standards in terms of the basic approach. Subsequently, we will give a comprehensive description of the individual technical constituents of MPEG-4. Emphasis will be put on the application and the benefit of the individual technological item. For a more detailed exposition of the technology, such as what might be requested by a developer or a frantic technology aficionado, we recommend you pick up one of the more technically oriented books on MPEG-4, a list of which is given in the reference list for this chapter. Finally, we will comment on few points where MPEG has been criticized.