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 a-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.