It is well known that cellulose is a very important and fascinating biopolymer, and an almost inexhaustible and renewable raw material. The trend towards these kind of resources and the tailoring of innovative products for science, medicine, and technology has led to a global renaissance of interdisciplinary cellulose research and the increased use of this abundant organic polymer over the last decade. This book presents fundamental and practical applications in the field of allomorphs of cellulose. It performs both a systematisation of the no elucidated elements in classical representations and the current hypotheses of the supramolecular organisation of cellulose allomorphs.