2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/39331We review several problems of conventional Grand Unification and some new approaches. In particular, we discuss strongly coupled Grand Unified Theories. Standard Model may emerge as a low energy effective theory of composite particles in these models. We construct a realistic model of this kind.14 pages, 2 eps figures. Lecture at the Baksan School ``Particles and Cosmology'', Baksan Valley, April 19 - 25, 1999High Energy Physics - Phenomenologytext