  This research announcement discusses our results on Gromov-Witten theory of
root gerbes. A complete calculation of genus 0 Gromov-Witten theory of
$\mu_{r}$-root gerbes over a smooth base scheme is obtained by a direct
analysis of virtual fundamental classes. Our result verifies the genus 0 part
of the so-called decomposition conjecture which compares Gromov-Witten theory
of \'etale gerbes with that of the bases. We also verify this conjecture in all
genera for toric gerbes over toric Deligne-Mumford stacks.
