When I was approached by Wiley to edit a book on ionic liquids in biotransformations and organocatalysis, the spontaneous question that quickly came to my mind was, is there a gap for such a book ? The fi eld of ionic liquids applied to biotransformations and organocatalysis has developed enormously during the last two decades. Therefore, the realization of a book that could gather, categorize, and provide an updated and complete state - of - the - art in these areas was clearly a demand. There are obviously several comprehensive reviews in the fi eld, but I think none of them can cover the topic(s) in their.