Non-commutative correspondences, duality and D-branes in bivariant K-theory

We describe a categorical framework for the classification of D-branes on non-commutative spaces using techniques from bivariant K-theory of C!-algebras. We present a new description of bivariant K-theory in terms of non-commutative correspondences which is nicely adapted to the study of T-duality in open string theory. We systematically use the diagram calculus for bivariant K-theory as detailed in our previous paper [12]. We explicitly work out our theory for a number of examples of noncommutativemanifolds