Liposomes have been widely considered as promising drug carriers for many years. Certain amphiphilic water-soluble polymers including amphiphilic derivatives of polyvinyl pyrrolidone (PVP) were found to be efficient steric protectors for liposomes in vivo. Amphiphilic PVP (SPVP) with molecular weight between 1800 and 6300 easily incorporates into the liposomal membrane and provides good steric protection for liposomes. The degree of this protection depends on both polymer concentration and molecular size of the PVP block. In order to investigate the influence of the hydrophobic and hydrophilic blocks on the properties of the resulting polymers, and their ability to provide steric protection, we have performed dynamic light scattering experiments (DLS) in which we measure the temporal autocorrelation function of fluctuations in the scattered intensity resulting from the diffusive motion of the particles. All SPVP derivatives form stable micelles in water solution.