  I describe the current status of MCnet tools for validating the performance
of event generator simulations against data, and for tuning their
phenomenological free parameters. For validation, the Rivet toolkit is now a
mature and complete system, with a large library of prominent benchmark
analyses. For tuning, the Professor system has recently completed its first
tunes of Pythia 6, with substantial improvements on the existing default tune
and potential to greatly aid the setup of new generators for LHC studies.
