2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/137129We study in this paper some connections between the Fraisse theory of amalgamation classes and ultrahomogeneous structures, Ramsey theory, and topological dynamics of automorphism groups of countable structures.73 pages, LaTeX 2e, to appear in Geom. Funct. AnalLogicDynamical Systems03C15; 05D10; 37B05text