NON-ABELIAN T-DUALITY FOR OPEN STRINGS

In the first part of the talk we discuss T-duality for a free boson on a world sheet with boundary in a setting suitable for the generalizat ion to non-trivial backgrounds. The gauging method as well as the cano nical transformation are considered. In both cases Dirichlet strings a s T-duals of Neumann strings arise in a generic way. In the second par t the gauging method is employed to construct the T-dual of a model wi th non-abelian isometries.