  The non-perturbative behavior of the N=2 supersymmetric Yang-Mills theories
is both highly non-trivial and tractable. In the last three years the valuable
progress was achieved in the instanton counting, the direct evaluation of the
low-energy effective Wilsonian action of the theory. The localization technique
together with the Lorentz deformation of the action provides an elegant way to
reduce functional integrals, representing the effective action, to some finite
dimensional contour integrals. These integrals, in their turn, can be converted
into some difference equations which define the Seiberg-Witten curves, the main
ingredient of another approach to the non-perturbative computations in the N=2
super Yang-Mills theories. Almost all models with classical gauge groups,
allowed by the asymptotic freedom condition can be treated in such a way. In my
talk I explain the localization approach to the problem, its relation to the
Seiberg-Witten approach and finally I give a review of some interesting
results.
