  We prove that the complete kernel for the high energy evolution in QCD must
be selfdual. The relevant duality transformation is formulated in precise
mathematical terms and is shown to transform the charge density into the
functional derivative with respect to the single-gluon scattering matrix. This
transformation interchanges the high and the low density regimes. We demostrate
that the original JIMWLK kernel, valid at large density is indeed dual to the
low denisity limit of the complete kernel derived recently in hep-ph/0501198.
