  The muon g-2 collaboration has measured the anomalous magnetic g value of the
positive muon to within a relative uncertainty of 0.7 parts per million. The
result, a_{\mu^+} = 11 659 204(7)(5) x 10^{-10} is in good agreement with the
preceding data on a_{\mu^+} and a_{\mu^-} and has about twice smaller
uncertainty. The measurement tests standard model theory, which at the level of
the experimental uncertainty involves quantum electrodynamics, quantum
chromodynamics, and electroweak interaction in significant ways. The analysis
of the anomalous magnetic g value of the negative muon is well underway.
