  We develop a supersymmetric representation of spin operators which unifies
the Schwinger and Abrikosov representations of SU(N) spin operators, allowing a
second-quantized treatment of representations of the SU(N) group with both
symmetric and antisymmetric character. By applying this to the SU(N) Kondo
model, we show that it is possible to develop a controlled treatment of both
Magnetism and the Kondo effect within a single large N expansion.
