2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/10529We review the most outstanding issues related to the study of the morphology of the Horizontal Branch (HB) in the Color-Magnitude Diagrams of Galactic Globular Clusters and its use as age indicator. It is definitely demonstrated (see also Bolte, this meeting) that age cannot be the only 2nd-P driving the HB morphology. Other candidate 2nd-Ps are briefly examined, with special attention to the possible influence of cluster stellar density.10 pages, Latex, 4 encapsulated postscript figures, ASP Conf. macros included - review presented at the Meeting "The Galactic Halo Inside and Out", Tucson, october 1995, ASPCS vol. 92, pag. 221Astrophysicstext