  In this talk I give an overview of the work done during the last 15 years in
collaboration with the late Adrian Patrascioiu. In this work we accumulated
evidence against the commonly accepted view that theories with nonabelian
symmetry -- either two dimensional nonlinear $\sigma$ models or four
dimensional Yang-Mills theories -- have the property of asymptotic freedom (AF)
usually ascribed to them.

High Energy Physics - Theory