Amphiphilic statistical copolymer samples of sodium 2-(acrylamido)-2-methylpropanesulfonate and n-hexyl methacrylate with different degrees of polymerization and compositions were prepared by reversible addition - fragmentation chain transfer copolymerization, and their self-aggregating structure in 0.1 M aqueous NaCl was studied by light scattering, fluorescence, viscometry, and size exclusion chromatography. Major components of the copolymer samples were aggregates consisting of 2-7 polymer chains and possessing 1-5 hydrophobic microdomains, depending on the degree of polymerization and composition.