2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/66537It is well-known that an effective orbifold M (one for which the local stabilizer groups act effectively) can be presented as a quotient of a smooth manifold P by a locally free action of a compact lie group K. We use the language of groupoids to provide a partial answer to the question of whether a noneffective orbifold can be so presented. We also note some connections to stacks and gerbes.19 pagesAlgebraic TopologyDifferential GeometrySymplectic Geometry58H05; 57S10, 18F99text