  We consider strongly interacting supersymmetric gauge theories which break
dynamically the GUT symmetry and produce the light Higgs doublets naturally.
Two models we proposed in the previous articles are reanalyzed as two phases of
one theory and are shown to have desired features. Furthermore, employing
nonabelian duality proposed recently by Seiberg, we study the dual theory of
the above one and show that the low-energy physics of the original and dual
models are the same as expected. We note that the Higgs multiplets in the
original model are regarded as composite states of the elementary hyperquarks
in its dual theory. Theories with other hypercolors and similar matter contents
are also analyzed in the same way.
