- A successive refinement coding scheme for the Wyner-Ziv problem which consisted of multi-stage encoders and decoders was discussed. In this scheme, the decoders used all the information generated from previous encoding stages and the side information, which was different from stage to stage. A scheme is successively refinable if the rate-distortion pair associated with any stage falls on the same Wyner-Ziv rate-distortion curve given the corresponding side information. It was proved that the Wyner-Ziv problem for Gaussian sources had no rate loss. A layered coding scheme using scalar quantization and Slepian-Wolf coding of bit planes based on LDPC codes was also demonstrated.