The second edition of this manual has been comprehensively revised and extended in certain parts. Since the first edition was published six years ago, there have been vital changes chiefly in the use of synthetic stored product protectants - including fumigation - or these are due to follow in the near future. Requirements for approval in registration procedures for plant protection agents and methods have become more stringent. This was a reaction to increasingly critical attitudes of the consumer as regards residues in foodstuffs in general and culminates in the demand for introduction of zero tolerance. In addition to this, products commonly used over many years have gradually been taken from the market either due to damaging effects on human health (e.g. Dichlorvos), or on the environment (e.g. methyl bromide) becoming evident, or such have been feared. With widespread species of pest becoming increasingly resistant to many products, their application is more and more limited (e.g. Malathion). In recent years, there has been clear progress in the search for alternative methods of post-harvest protection. The great breakthrough achieved in biological pest control was the introduction of an antagonist to farm-level stores in Africa to contain the population of the Larger Grain Borer. Development of inert dust has also advanced to the stage where it can be applied practically. This and other new developments have been taken into consideration during revision of the manual.