In-plane electronic transport in thin layered magnetic structures composed of two ferromagnetic films separated by a nonmagnetic spacer is analyzed theoretically in the Born approximation. Particular attention is paid to the role of interface roughness in the giant magnetoresistance (GMR) effect. The analysis applies to self-affine interfaces described by thek-correlation model. Our results show that GMR is sensitive to the roughness exponentH(0⩽H⩽1)in a manner that depends on spin asymmetries for bulk and interfacial scattering. The limit of low electron concentration is also considered. ©1997 American Institute of Physics.