  Coupled-channel dynamics for scattering and production processes in
partial-wave amplitudes is discussed from a perspective that emphasizes
unitarity and analyticity. We elaborate on several methods that have driven to
important results in hadron physics, either by themselves or in conjunction
with effective field theory. We also develop and compare with the use of the
Lippmann-Schwinger equation in near-threshold scattering. The
final(initial)-state interactions are discussed in detail for the elastic and
coupled-channel case. Emphasis has been put in the derivation and discussion of
the methods presented, with some applications examined as important examples of
their usage.
