B meson form factors and exclusive decays

We present results for the B → π and D → π form factors derived from QCD sum rules on the light-cone. Our predictions are compared with experiment and used to extract the quark mixing parameter |Vub| from a recent CLEO measurement of B → πl+ν. Furthermore, we discuss the factorization approximation for exclusive nonleptonic matrix elements, and describe a first QCD estimate of the nonfactorizable contribution to the amplitude of B → JψK.