  The measurements of the mean lifetime of the tau lepton are reviewed. The
conditions for measuring the lifetime at various e+e- colliders are compared
and the analysis methods are briefly described. The new developments since the
previous Workshop on Tau Lepton Physics are listed. The world average is
tau_tau = 290.5 +- 1.0 fs. The LEP experiments dominate this average and have
analyzed nearly all of their data. In anticipation of the next era of precision
measurements at CLEO and the b factories, the important sources of systematic
errors and the treatment of systematic biases are discussed.
