Abstract
We construct the covariant action for the
N = 2 superstring in a ten-dimensional supergravity background. The flat superspace three-form needed for the construction of the Wess-Zumino term has a natural generalization in the curved superspace description of
N = 2,
d = 10 supergravity. We also discuss superstrings in
d = 3, 4 and 6 supergravity backgrounds.
