  We study the (spin-)Peierls transition in quasi-one-dimensional disordered
systems, treating the lattice classically. The role of kinks, induced thermally
and by disorder, is emphasized. For weak interchain interaction the kinks
destroy the coherence between different chains at a temperature significantly
lower than the mean-field Peierls transition temperature. We formulate the
effective Ising model, which describes such a transition, investigate the
doping dependence of the (spin-)Peierls transition temperature and discuss
several implications of the picture developed. The results are compared with
the properties of the spin-Peierls system CuGeO_3.
