Since the early 1970s the subject of biodegradable plastics has acquired a rapidly growing literature of academic research papers. It has also acquired a formidable volume of patent documentation and all this has been over­ whelmed by an astonishing quantity of serious media and political com­ ment. A new entrant into any technical arena w. ould, in most technologies, simply visit their technical library and pick up a text book on the subject in the expectation of absorbing the basic facts before launching into the daily task of updating and evaluating. Scientific conferences have produced many substantial volumes carrying the word 'biodegradable' on their covers, and there has even been a specialist monograph on the topic of bacterially produced polymers but, surprisingly, no book has yet emerged providing a general survey of the subject. Having devoted half my pro­ fessional career to the subject of biodegradable plastics I agreed to take on the editorial job of producing such a book when asked by the publisher. I knew that the task of finding expert specialists and persuading them to contribute dispassionate accounts of their specialisms would not be easy, but the difficulties that I have encountered were far greater than I expected. Some were simply too busy, others were involved in patent disputes or commercial negotiations. In giving an account of the work that I and my students carried out at BruneI University I believe that I have written in a manner that displays enthusiasm without prejudice.