This paper presents the ToCAI (Table of Content-Analytical Index, ToCAI) Description Scheme (DS) for content description of audio-visual documents. The original idea comes out from the structure used for technical books. Ones may easily understand a book sequential organization by looking at its table of contents while quickly retrieve elements of interest by means of the analytical index. This description scheme provides therefore a hierarchical description of the time sequential structure of a multimedia document (thanks to the ToC), suitable for browsing, together with an "Analytical Index" (AI) of audio-visual objects of the document, suitable for effective retrieval. Besides, two sub-description schemes for information about description generation and about the metadata associated to the document are also enclosed in the general DS. The detailed structure of the DS is also presented by means of UML notation and an application example is shown. Finally, some considerations about the adopted visual interface are made.