  We discuss the properties of two different types of infrared solutions of
Landau gauge Yang-Mills theory and argue for one of these (the 'scaling
solution'). We furthermore clarify the status of previously obtained results
from DSEs on a four-torus. Including quarks we discuss a relation between
confinement and dynamical chiral symmetry breaking based on the scaling
solution of Yang-Mills theory. An infrared singularity in the quark-gluon
vertex allows for a solution of the $U_A$(1) problem along the lines of a
mechanism suggested by Kogut and Susskind long ago.
