Cellulose, known as a fascinating biopolymer and a never ending-source of new sustainable materials, is attracting increasing attention in different fields owing to its abundance, biodegradability, unique physico-chemical properties, broad chemical modifying capacity, and formation of versatile semicrystalline (nano)morphologies. Recent publications address the use of vegetable cellulose and bacterial cellulose in combination with several other polymers to build cellulose-based functional materials. The applications of such materials range from wound healing and drug delivery to food packaging and fuel cells. Further development of these projects will profit from the deeper understanding the structure-properties relationships a task which our team has embraced and for which INS provides a unique view.