Calorons and fermion zero-modes

Calorons in the confined phase for SU(n) gauge theory, having a non-trivial Polyakov loop, "dissolve" in n monopole constituents for large enough instanton scale parameters. We discuss recent results for these caloron solutions and their fermion zero-modes, as well as the implications for lattice studies and comment on the possible influence of the constituent monopoles on the instanton size distribution.