Confinement and short distance physics

We consider non-perturbative effects at short distances in theories with co nfinement. The analysis is straightforward within the Abelian models in whi ch the confinement arises on classical level. In all cases considered (comp act U(1) in 3D and 4D, dual Abelian Higgs model) there are non-perturbative contributions associated with short distances which are due to topological defects. In QCD case, both classical and quantum effects determine the rol e of the topological defects and the theoretical analysis has not been comp leted so far. Generically, the topological defects would result in 1/Q(2) c orrections going beyond the standard Operator Product Expansion. We review existing data on the power corrections and find that the data favor existen ce of the novel corrections, at least at the mass scale of (1-2) GeV. We in dicate crucial experiments which could further clarify the situation on the phenomenological side. (C) 2000 Elsevier Science B.V. All rights reserved.