Using 1.79 fb-1 of data recorded by the CLEO II detector we have measu
red the absolute branching fraction for D0 --> K-pi+. The angular corr
elation between the pi+ emitted in the decay D+ --> D0pi+, and the je
t direction in e+e- --> ccBAR events, is used to determine the total n
umber of inclusive D0 mesons produced from this source. The subsequent
reconstruction of the decay chain D+ --> D0pi+, D0 --> K-pi+ allows
a measurement of the absolute D0 --> K-pi+ branching fraction. Correct
ing for decay radiation in the final state, we find B(D0 --> K-pi+) =
[3.95 +/- 0.08(stat)+/-0.17(syst)]%.