  The study of Dalitz plots of heavy-meson decays to multi-hadron final states
has received intensified interest by the possibility to gain access to
precision investigations of CP violation. A thorough understanding of the
hadronic final-state interactions is a prerequisite to achieve a highly
sensitive, model-independent study of such Dalitz plots. We illustrate some of
the theoretical tools, predominantly taken from dispersion theory, available
for these and related purposes, and discuss the low-energy decays omega, phi
--> 3pi in some more detail.
