Comment on nonperturbative effects in (B)over-bar->X-s gamma

Uncertainties in the theoretical prediction for the inclusive (B) over bar --> X-s gamma decay rate are discussed. We emphasize that there is no operator product expansion for this process. Nonetheless, some nonperturbative effects involving a virtual c (c) over bar loop are calculable using the operator product expansion. They give a contribution to the decay rate that involves the B meson matrix element of an infinite tower of operators. The higher dimension operators give effects that are only suppressed by powers of m(b) Lambda(QCD)/m(c)(2) similar to 0.6, but come with small coefficients. (C) 1997 Elsevier Science B.V.