  Recent discoveries in supersymmetric gauge theories have significant
implications for our understanding for QCD and of field theory in general. The
phases of N=1 supersymmetric QCD (SQCD) are discussed, and the possibility of
similar phases in non-supersymmetric QCD is emphasized. It is described how
duality in SQCD links many previously known duality transformations that were
thought to be distinct, including Olive-Montonen duality of N=4 supersymmetric
gauge theory and quark-hadron duality in (S)QCD. A link between Olive-Montonen
duality and the confining strings of (S)QCD is explained, in which a picture of
confinement via non-abelian monopole condensation --- a generalized dual
Meissner effect --- emerges explicitly. In this picture, unlike previous ones,
the confining flux tubes carry the correct Z_N discrete charges. A number of
studies of these subjects, which could be carried out using lattice gauge
theory, are proposed.
