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Higher symmetries enter naturally in various geometrical settings: for example,$C^*$-algebras form a 2-category,thus 2-groupoids acts naturally on them.Thus it is considerable to bring higher groupoids as symmetry in the world of non-commutative geometry.Properness of topological groupoid makes it easy to transfer corresponding objects from differentiable geometry to non-commutative geometry.This right away clarifies several existing concepts such as twisted actions in the sense of Green or Busby–Smith therein.Moreover,via desingularization,2-groupoid also helps in the case of Connes example on non-Hausdorff 1-groupoids coming from foliations.Our long term goal is to use 2-groupoids to overcome some difficulties in Baum-Connes conjecture.