  We present a field theory for the statistics of charge and current
fluctuations in diffusive systems. The cumulant generating function is given by
the saddle-point solution for the action of this field theory. The action
depends on two parameters only: the local diffusion and noise coefficients,
which naturally leads to the universality of the transport statistics for a
wide class of multi-dimensional diffusive models. Our theory can be applied to
semi-classical mesoscopic systems, as well as beyond mesoscopic physics.
