Diffraction gratings have been encoded in bulk Cd(0.8)Zn(0.2)Te:In samples by near-band-gap excitation. The photoinduced index change is associated with persistent photoconductivity resulting from ionization of DX centers. The gratings have a thickness of 1.7 mm, as evinced by Bragg selectivity during the readout process. Encoded grating are shown to be persistent for sufficiently low temperatures and are not erased by subsequent writing of more gratings.