  An experimental search for an electric-dipole moment (EDM) of the neutron has
been carried out at the Institut Laue-Langevin (ILL), Grenoble. Spurious
signals from magnetic-field fluctuations were reduced to insignificance by the
use of a cohabiting atomic-mercury magnetometer. Systematic uncertainties,
including geometric-phase-induced false EDMs, have been carefully studied. Two
independent approaches to the analysis have been adopted. The overall results
may be interpreted as an upper limit on the absolute value of the neutron EDM
of |d_n| < 2.9 x 10^{-26} e cm (90% CL).
