This paper gives an overview of Part 1 of ISO/IEC 15939 (MPEG-7 Systems), It first presents the objectives of the MPEG-7 Systems activity. In the MPEG-1 and MPEG-2 standards, "Systems" referred only to overall architecture, multiplexing, and synchronization. In MPEG-4, in addition to these issues, the Systems part encompasses interactive scene description, content description, and programmability, MPEG-7 brings new challenges to the Systems expertise, such as languages for description representation, binary representation of descriptions, and delivery of descriptions either separate or jointly with the audio-visual content. The paper then presents the description of the MPEG-7 Systems specification, starting from the general architecture up to the description of the individual MPEG-7 Systems toots. Finally, a conclusion describes the status of the standardization effort, as well as future extensions of the specification.