  We investigate the quark structure of D and B mesons in the framework of a
constituent quark model. To this end, we assume a scalar confining and a one
gluon exchange (OGE) potential. The parameters of the model are adopted to
reproduce the meson mass spectrum. From a fit to ARGUS and CLEO data on B->D*lv
semileptonic decay we find for the Cabbibo Kobayashi Maskawa matrix element
Vcb=0.036+-0.003. We compare our form factors to the pole dominance hypothesis
and the heavy quark limit. For non-leptonic decays we utilize factorization and
for B->D*X decays we find a1 = 0.96+-0.05, and a2=0.31+-0.03.
