  The uncertainty in jet energy scale is one of the dominating systematic
errors for many measurements at hadron colliders - most notably for the
measurement of the top-quark-mass, inclusive jet cross section measurements and
last but not least for events with large missing transverse energy as expected
in searches beyond the standard model. This talk will review the approaches
taken at Tevatron towards controlling the jet energy scale and discuss
prospects for the LHC experiments.
