This book presents data on thermal relaxation properties of chitosan neutralised and non-neutralised films as a function of water content using dynamical mechanical analysis and dielectric spectroscopy in the temperature range from 20 to 250°C. Three relaxation processes have been observed in different temperature and frequency ranges. For the first time, the low frequency á-relaxation associated with the glass-rubber transition, which relates to a plasticising effect of water, has been detected by this technique in both chitosan forms in the temperature range 20-70°C and for moisture contents between 0.5 to 10 wt %. This book discusses various relaxation processes in chitosan films.