  Color reconnection and Bose-Einstein correlations not only can have an
influence on the measurement of the W-mass in the fully hadronic W+W- decay
channel at LEP2, but also can give essential information on the structure of
the QCD vacuum and the space-time development of a q_1\bar q_2 system. Recent
developments are critically analyzed, with particular emphasis on the models
used in this field. More sensitive variables are needed to distinguish between
color reconnection models, while more experimental knowledge has to be built
into the Bose-Einstein models and, above all, these two closely related
phenomena have to be treated in common. Both effects are determined by the
space-time overlap of the W+ and W- decay products. Vital experimental
information on the space-time development of the decay of the q_1\bar q_2
system is becoming available from the high-statistics data on hadronic Z decay
and models will have to be able to explain this evidence before being used to
predict interference effects in hadronic W+W- decay.
