Exact Superpotentials in Four Dimensions
  Supersymmetric gauge theories in four dimensions can display interesting non-perturbative phenomena. Although the superpotential dynamically generated by these phenomena can be highly nontrivial, it can often be exactly determined. We discuss some general techniques for analyzing the Wilsonian superpotential and demonstrate them with simple but non-trivial examples. 
K. Intriligator, R.G. Leigh and N. Seiberg