Langmuir-Blodgett-Kuhn (LBK) multilayer assemblies of "hairy-rod" polyglutamates with stiff main chains and flexible side chains containing photochromic azo units exhibit a highly optically anisotropic structure when the azo molecules are in the trans form and a nearly optically isotropic structure when the azo molecules are in the cis form. The trans <-> cis photoisomerization of the azo molecules switches them between a highly oriented trans cofiguration and a bend cis configuration, thus turning the anisotropy "on" and "off"; the corresponding optical order parameter changes by about 1 order of magnitude. In contrast to spun-cast polymer films containing azobenzene units, photoselection under polarized light irradiation does not occur in these LBK structures. The study of the electronic density distribution of these films shows that-a remarkable variation in the LBK structures’ stability comes with a seemingly small change in the side-chain structure. A stable LBK double-layer structure has been prepared, and its physical origin has been discussed.