  We perform non-abelian T-duality for a generic Green-Schwarz string with
respect to an isometry (super)group G, and we derive the transformation rules
for the supergravity background fields. Specializing to G bosonic, or G
fermionic but abelian, our results reproduce those available in the literature.
We discuss also continuous deformations of the T-dual models, obtained by
adding a closed B-field before the dualization. This idea can also be used to
generate deformations of the original (un-dualized) model, when the 2-cocycle
identified from the closed B is invertible. The latter construction is the
natural generalization of the so-called Yang-Baxter deformations, based on
solutions of the classical Yang-Baxter equation on the Lie algebra of G and
originally constructed for group manifolds and (super)coset sigma models. We
find that the deformed metric and B-field are obtained through a generalization
of the Seiberg-Witten map. When applied to integrable sigma models these
deformations preserve the integrability.
