Poly(dianilino phosphazene) has been synthesized from hexachlorocyclotriphosphazene by two different methods, bulk and solution. Several fractions, with polydispersity ratio ranging from 1.8 to 2.4, were obtained by fractional precipitation and characterized by viscometry and size exclusion chromatography (s.e.c.) using simultaneously refractive index and multi-angle light scattering detectors. From these data the solution behaviour of the polymer is discussed.