We approach Mackenzie’s
ℒ𝒜-groupoids from a supergeometric point of view by introducing Q-groupoids,
which are groupoid objects in the category of Q-manifolds. There is a faithful functor
from the category of ℒ𝒜-groupoids to the category of Q-groupoids. We associate to
every Q-groupoid a double complex that provides a model for the Q-cohomology of
the classifying space. As examples, we obtain models for equivariant Q- and orbifold
Q-cohomology, and for equivariant Lie algebroid and orbifold Lie algebroid
cohomology. We obtain double complexes associated to Poisson groupoids and
groupoid-algebroid “matched pairs”.