  I describe an application of Wilson Renormalization group to the real time
formalism of finite temperature field theory. The approach has two nice
features: 1) the RG flow equations describe non-perturbatively the effect of
thermal fluctuations only, and, 2) the flow is gauge invariant. I then describe
the application of the method to the study of the gluon self-energy in SU(N),
and present results for the computation of the Debye and magnetic screening
masses.
