  We study the WZW model based on the centrally extended 2D de Sitter algebra.
We obtain the spacetime metric and its explicitly conformally flat expression.
The symmetries of the spacetime are found by identifying the Killing vectors
with the group generators. The energy-momentum tensor obtained from the
affine-Sugawara construction agrees with that from the more conventional
approach. The exact center charge agrees to one-loop order with the one-loop
beta function equations. We have also studied the representations of the
corresponding enveloping Virasoro algebra.
