Abstract. This paper is devoted to a study of multivariate nonhomogeneous refinement equations of the form. . , gr) T is a given vector of functions on R s , M is an s × s dilation matrix, and a is a finitely supported refinement mask such that each a(α) is an r × r (complex) matrix. Let φ 0 be an initial vector in (L 2 (R s )) r . The corresponding cascade algorithm is given byIn this paper we give a complete characterization for the L 2 -convergence of the cascade algorithm in terms of the refinement mask a, the nonhomogeneous term g, and the initial vector of functions φ 0 .