We present evidence for soft gluon interference, as required by QCD. T
his interference is expected to manifest itself in an angular ordering
of the gluons radiated within a jet. Using hadronic decays of the Z b
oson in the L3 detector at LEP, we compare variables sensitive to such
an angular ordering, namely the energy-energy correlation asymmetry a
nd the newly introduced particle-particle correlation asymmetry, with
the predictions of various parton shower models. Only those models whi
ch incorporate the expected interference agree with the data.