Rare B decays beyond B-> Xs gamma

Abstract

I discuss recent progress in our understanding of exclusive rare and semileptonic decays. I show the impact of HQET when combined with the predictions in the Large Energy Limit of QCD, focusing first on applications to $B\to K^{\ast }{\ell }^{+}{\ell }^{+}$. I also discuss the constraints on semileptonic form-factors that appear in HQET/LEET with the use of radiative decay data, and update these to include the effects of next-to-leading order contributions in $B\to K^{\ast }\gamma$, as well as the latest data.

Comments: 11 pages, 2 ps figures. Invited talk at Heavy Flavors 9, Caltech, Pasadena, Sept. 10-13 2001