  A general construction of integrable hierarchies based on affine Lie algebras
is presented. The models are specified according to some algebraic data and
their time evolution is obtained from solutions of the zero curvature
condition. Such framework provides an unified treatment of relativistic and non
relativistic models. The extension to the construction of supersymmetric
integrable hierarchies is proposed. An explicit example of N=2 super mKdV and
sinh--Gordon is presented.
