Carbohydrate chemistry is a rapidly growing research and development area with great potential for future achievements due to the eminent importance of carbohydrates in biochemistry and biology and the strong impact of gly- sciences in these fields. One of the most important methods of carbohydrate transformation in terms of commercial significance is the conversion of sugars into high-added-value epimers or isomers such as the enzymatic transfor- tion of d-glucose into d-fructose or the base induced isomerisation of lactose into lactulose. In addition to these industrial processes, quite a range of methods has become available to transform simple sugars into valuable intermediates, building blocks and sophisticated products. Consequently, a compilation of - portant but quite diverse methods in one book appeared to be a worthwhile task. Quite a few of the authors have made significant discoveries in the area under consideration. Others have contributed important and innovative extensions taking one or the other method to even higher levels of sophistication. The classical method of epimerisation, the Lobry de Bruyn - Alberda van Ekenstein rearrangement has been treated by S. Angyal, the expert in the field of free sugars and their interconversions. L. Petrus? and co-authors have contr- uted a first-hand experience based chapter on the Bรญlik reaction, which was discovered in Bratislava and is an important approach to rare sugars on a c- mercial basis. Another, more recently developed method, the epimerisation of free sugars catalysed by nickel (II)/ethylene diamine complexes, has been - viewed by S. Osanai.