A survey of the data reported in the literature on the dilute solution characterization of polyphosphazenes is presented. There are relatively few studies dealing with this kind of characterization, at least in comparison with the enormous amount of work devoted to the synthesis, solid-state properties and possible practical applications of these materials. Furthermore the analyses published to date give surprising and often contradictory results which indicate that the solution properties of these polymers are difficult to measure and not yet well understood. High polydispersity of the samples, formation of intermolecular aggregations and branching are the problems more frequently invoked to explain the experimental results. Some conclusions are presented that could facilitate future characterizations of these polymers.