  We explore the capability of the Tevatron and LHC to place limits on the
possible existence of flavor-independent $q \bar q \gamma\gamma$ contact
interactions which can lead to an excess of diphoton events with large
invariant masses. Assuming no departure from the Standard Model is observed, we
show that the Tevatron will eventually be able to place a lower bound of
0.5-0.6 TeV on the scale associated with this new contact interaction. At the
LHC, scales as large as 3-6 TeV may be probed with suitable detector cuts and
an integrated luminosity of $100 fb^{-1}$.
