Differential dynamic content delivery with a participant alterable session copy of a user profile. Typical embodiments include providing a session document for a presentation, where the session document includes a session grammar and a session structured document; providing a session copy of a participant's user profile including a user classification; receiving, from the participant, a user classification instruction to change a user classification in the session copy of the participant's user profile; changing the user classification in the session copy of the participant's user profile in dependence upon the participant's user classification instruction; selecting from the session structured document a classified structural element in dependence upon a user classification in the session copy of the participant's user profile in the presentation; and presenting the selected structural element to the participant.