  We describe the universal Monte-Carlo event generator WHIZARD.
  The program automatically computes complete tree-level matrix elements,
integrates them over phase space, evaluates distributions of observables, and
generates unweighted event samples that can be used directly in detector
simulation. There is no principal limit on the process complexity; using
current hardware, the program has successfully been applied to hard scattering
processes with up to eight particles in the final state. Matrix elements are
computed as helicity amplitudes, so spin and color correlations are retained.
The Standard Model, the MSSM, and many alternative models such as Little Higgs,
anomalous couplings, or effects of extra dimensions or noncommutative SM
extensions have been implemented. Using standard interfaces to PDF,
beamstrahlung, parton shower and hadronization programs, WHIZARD generates
complete physical events and covers physics at hadron, lepton, and photon
colliders.
