The failure of the standard slowing-down solutions to reproduce the detailed flux distribution both in and far below a resonance is discussed. To first order, the neutron distribution in energy is explicitly symmetric about the resonance center. Higher-order approximations, however, reveal the asymmetry in the spectral distribution. The direction of the spectral shift, as well as the degree of asymmetry, depends on the resonance parameters. There is, in particular, a competition between absorption and scattering in the resonance which directly affects the spectral asymmetry. The asymptotic distribution far below the resonance is unity instead of equal to the resonance escape probability. This difficulty may be overcome by formulating the problem in terms of the Placzek solution.