%0 Journal Article %T Brauer groups and quotient stacks %A D. Edidin %A B. Hassett %A A. Kresch %A A. Vistoli %J Mathematics %D 1999 %I arXiv %X A natural question is to determine which algebraic stacks are qoutient stacks. In this paper we give some partial answers and relate it to the old question of whether, for a scheme X, the natural map from the Brauer goup (equivalence classes of Azumaya algebras) to the cohomological Brauer group (the torsion subgroup of $H^2(X,{\mathbb G}_m)$ is surjective. %U http://arxiv.org/abs/math/9905049v3