I discuss the renormalization of the shape-function describing the effective mass distribution of the b quark inside a B meson in semi-inclusive non-charmed B meson decays. An effective theory is required in the soft and collinear kinematical regions. It is enlightened the interplay between the choice of the effective theory and the regularization procedures.

PACS numbers: 13.25.Hw, 12.39.Hg, 11.10.Gh