  We interpret the chiral WZNW model with general monodromy as an infinite
dimensional quasi-Hamiltonian dynamical system. This interpretation permits to
explain the totality of complicated cross-terms in the symplectic structures of
various WZNW defects solely in terms of the single concept of the
quasi-Hamiltonian fusion. Translated from the WZNW language into that of the
moduli space of flat connections on Riemann surfaces, our result gives a
compact and transparent characterisation of the symplectic structure of the
moduli space of flat connections on a surface with k handles, n boundaries and
m Wilson lines.
