The muon (g - 2) experiment E821 is currently in progress at Brookhaven National Laboratory. Four data-taking runs for positive muons and one run for negative muons were successfully accomplished in 1997-2000 and 2001, respectively. Results of the 1997-2000 runs have been published, thus completing our experiment for mu(+). Data analysis for the 2001 run for mu(-) is currently in progress. To provide measurement of a(mu)- = 1/2(g - 2)(mu)- at the same level of accuracy as for a(mu)+ = 1/2(g - 2)(mu)+, we would need one more data-taking run.
