2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/54706One of the perspectives in modern quantum field and string theory is related with the attempts to go beyond the perturbation theory. It turns out that a key principle in the formulation of all known non-perturbative results is {\it integrability}, i.e. arising of the structures of completely integrable systems. I discuss several important steps in this direction and speculate on its further possible development.5 pages, LaTeX, no figures; based on a talk given at the Second International Sakharov Conference, 20-24 May 1996, Moscow, RussiaHigh Energy Physics - Theorytext