Instantons and perturbative analysis in supersymmetric gauge theories

This dissertation reviews various topics concerning the dynamics of extended supersymmetric gauge theories (SYM) in four dimensions. The book is divided in two parts. The first one which comprises chapter 1 and 2 regards the perturbative inspection of a highly non trivial super--conformal model. The second part which comprises chapter 3 and 4 contains some topics concerning instanton computations in supersymmetric gauge theories.