Duality Symmetries and Supersymmetry Breaking in String   Compactifications
  We discuss the spontaneous supersymetry breaking within the low-energy effective supergravity action of four-dimensional superstrings. In particular, we emphasize the non-universality of the soft supersymmetry breaking parameters, the $\mu$-problem and the duality symmetries. 
G. Lopes Cardoso, D. Lust and Thomas Mohaupt