  We calculate the very high energy (sub-GeV to TeV) inverse Compton emission
of GRB afterglows. We argue that this emission provides a powerful test of the
currently accepted afterglow model. We focus on two processes: synchrotron
self-Compton (SSC) emission within the afterglow blast wave, and external
inverse Compton (EIC) emission which occurs when flare photons (produced by an
internal process) pass through the blast wave. We show that if our current
interpretations of the Swift XRT data are correct, there should be a canonical
high energy afterglow emission light curve. Our predictions can be tested with
high energy observatories such as GLAST, Whipple, H.E.S.S. and MAGIC. Under
favorable conditions we expect afterglow detections in all these detectors.
