  We explicitly obtain the generalization of the Ehlers transformation for
stationary axisymmetric Einstein equations to string theory. This is
accomplished by finding the twist potential corresponding to the moduli fields
in the effective two dimensional theory. Twist potential and symmetric moduli
are shown to transform under an $O(d,d)$ which is a manifest symmetry of the
equations of motion. The non-trivial action of this $O(d,d)$ is given by the
Ehlers transformation and belongs to the set $O(d) \times O(d)\over O(d) $.
