  I give an overview over some work on rigorous renormalization theory based on
the differential flow equations of the Wilson-Wegner renormalization group. I
first consider massive Euclidean $\phi_4^4$-theory. The renormalization proofs
are achieved through inductive bounds on regularized Schwinger functions. I
present relatively crude bounds which are easily proven, and sharpened versions
(which seem to be optimal as regards large momentum behaviour). Then
renormalizability statements in Minkowski space are presented together with
analyticity properties of the Schwinger functions. Finally I give a short
description of further results.
