2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/130958The aim of this paper is to give an alternative proof of a theorem about the existence of contact structures on five-manifolds due to Geiges. This theorem asserts that simply-connected five-manifolds admit a contact structure in every homotopy class of almost contact structures. Our proof uses the open book construction of Giroux.15 pages, 2 figures; typos corrected, used simpler argument for section 3; to appear in Annales de l'institut FourierSymplectic GeometryGeometric Topology53D35, 57R17text