We report on a search for the rare decay K-L --> pi(0)nu(nu)over-bar in the
KTeV experiment at Fermilab. We searched for two-photon events whose kinem
atics were consistent with an isolated pi(o) coming from the decay K-L -->
pi(0)nu(nu)over-bar. One candidate event was observed, which was consistent
with the expected level of background. An upper limit on the branching rat
io was determined to be B(K-L --> pi(o)nu(nu)over-bar) less-than 1.6 x 10(-
6) at the 90% confidence level. (C) 1999 Published by Elsevier Science B.V.
All rights reserved.