2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/49599Recent developments in supersymmetric unified theories are reviewed, with particular emphasis on supersymmetric grand unification and a brief discussion of recent ideas about extra dimensions.77 pages; four figures; Lectures presented at the Trieste summer school in July, 1999; UMD-PP-00-038; (parts of the article appeared before in the TASI97 lectures by the author); typos corrected and one reference addedHigh Energy Physics - Phenomenologytext