  We study BPS saturated domain walls in the supersymmetric SU(2) gauge theory.
For a theory with a very light adjoint scalar (mass <~ Lambda/400) we use the
perturbed N=2 Seiberg-Witten theory to calculate the actual field configuration
of the domain wall. The wall has a sandwich-like five-layer structure of three
distinct phases -- electric confinement, Coulomb and oblique confinement --
separated by two separate transition regions. For larger scalar masses, the
three-phase structure disappears and the Seiberg-Witten theory becomes
inadequate because of two major problems: First, the higher-derivative
interactions between the light fields become relevant and second, both the
magnetic monopole condensate and the dyon condensate show up in the same region
of space, a phenomenon indescribable in terms of a local field theory.
Nevertheless, we argue that the BPS saturated domain wall continues to exist in
this regime and give a qualitative description of the scalar and gaugino
condensates. Finally, we discuss the domain walls in MQCD and translate the BPS
conditions into coupled non-linear differential equations.
