  We discuss factorization in exclusive radiative leptonic B->\gamma e\nu
decays using the soft-collinear effective theory. The form factors describing
these decays can be expanded in a power series in Lambda/E_\gamma with E_\gamma
the photon energy. We write down the most general operators in the effective
theory which contribute to the form factors at leading order in
Lambda_QCD/E_\gamma, proving their factorization into hard, jet and soft
contributions, to all orders in alpha_s.
