Abstract
The review presents the experimental results of studies on the physicochemical and complex-forming properties of synthetic polyampholytes in dilute solution. The similarity of the behaviour of polyampholytes at the isoelectric point and polyelectrolyte complexes is demonstrated. Questions concerning the complex formation reactions of polyampholytes with inorganic and organic ions, polyelectrolytes, and proteins are discussed. The role of competing interactions in the formation of intramolecular and intermolecular polycomplexes is considered. The bibliography includes 82 references.