  We review the theory of quiver bundles over a K\"ahler manifold, and then
introduce the concept of generalized quiver bundles for an arbitrary reductive
group G. We first study the case when G=O(V) or Sp(V), interpreting them as
orthogonal (resp. symplectic) bundle representations of the symmetric quivers
introduced by Derksen-Weyman. We also study supermixed quivers, which
simultaneously involve both orthogonal and symplectic symmetries. Finally, we
discuss Hitchin-Kobayashi correspondences for these objects.
