2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/222828We specify exactly which groups can act geometrically on CAT(0) spaces whose visual boundary is homeomorphic to either a circle or a suspension of a Cantor set.This is the version published by Algebraic & Geometric Topology on 4 May 2006Geometric TopologyGroup Theory20F65, 57M60text