Abstract: A human viewing temporally-dimensioned content of a multimedia document through use of a computer can add substantive content to temporally-dimensioned content of the multimedia document to thereby annotate, comment upon, and augment the multimedia document. Thus, a multimedia document becomes a basis for collaborative work. The substantive content added by the viewing user is in the form of a temporal annotation which identifies a particular relative time in temporally-dimensioned content of the multimedia document and which includes user-authored content provided by the viewing user. Display of the multimedia document includes presentation of the temporal annotations created by the user. A graphical user interface enables the user to select a temporal annotation from a list and immediately proceed to presentation of the multimedia document such that temporally-dimensioned content is presented at the particular relative time represented by the selected temporal annotation.