We outline a method of relating the quantum effective action and the ground
state wave function of a field theory. This method, along with a
gauge-invariant mass term and the previously obtained vacuum wave function, is
used to arrive at the leading terms of the 3d-covariant quantum effective
action for the Yang-Mills theory in three (or 2+1) dimensions. Some features of
this effective action are also discussed.Comment: 10 pages, Invited talk at the International Workshop on QCD Green's
functions, Confinement and Phenomenology, QCD-TNT II, September 201