This work is primarily designed for any person or organization in charge of assessment of the quality of natural resources and of pollution prevention.

The International Working Conference on Stored Product Protection (IWCSPP), held every four years, is the premier world forum for presentation of research results bearing on the safe storage of durable foodstuffs, particularly cereal grains, pulses, and oilseeds. The 6th IWCSPP was held in Canberra, Australia from 17-23 April 1994, under the auspices of CSIRO, the Australian Centre for International Agricultural Research (ACIAR), and the Australian grain handling and storage industry. These two volumes present the proceedings of the conference. There were over 400 participants. Apart from Australia, there were substantial contingents from Brazil, Canada, China, France, Germany, India, Indonesia, Israel, Pakistan, the Philippines, the UK and the USA. A further 20 countries were represented. The overall objective was to present advances in research and development on the preservation of stored durable commodities since the 5th IWCSPP held in Bordeaux, France 1990. Much had happened in the intervening four years: the role of methyl bromide had come under scrutiny; pressure from consumers and environmentalists to reduce chemical additives to foodstuffs had become more intense; that mycotoxin contamination of food and feedstuffs was a serious threat to human and animal health had gained general acceptance. Recognizing these and related issues the theme "Stored product protection - a Time of Challenge" was adopted for the conference. Some 250 papers were presented. These proceedings volumes contain, in addition to most of those papers, reports of a series of workshops on specialist topics - trapping, application of inert dusts, extension and small-scale and farm storage, standards, expert systems and appropriate storage - that were also part of the scientific program. Overall, the volumes provide an essential update for entomologists, plant pathologists, engineers and others concerned with stored product protection.

Bruce E. Tabashnik and Richard T. Roush Pesticide resistance is an increasingly urgent worldwide problem. Resistance to one or more pesticides has been documented in more than 440 species of insects and mites. Resistance in vectors of human dise8se, particularly malaria-transmit ting mosquitoes, is a serious threat to public health in many nations. Agricultural productivity is jeopardized because of widespread resistance in crop and livestock pests. Serious resistance problems are also evident in pests of the urban environ ment, most notably cockroaches. Better understanding of pesticide resistance is needed to devise techniques for managing resistance (Le. , slowing, preventing, or reversing development of resistance in pests and promoting it in beneficial natural enemies). At the same time, resistance is a dramatic example of evolution. Knowledge of resistance can thus provide fundamental insights into evolution, genetics, physiology, and ecology. Resistance management can help to reduce the harmful effects of pesticides by decreasing rates of pesticide use and prolonging the efficacy of environmentally safe pesticides. In response to resistance problems, the concentration or frequency of pesticide applications is often increased. Effective resistance management would reduce this type of increased pesticide use. Improved monitoring of resis tance would also decrease the number of ineffective pesticide applications that are made when a resistance problem exists but has not been diagnosed. Resistance often leads to replacement of one pesticide with another that is more expensive and less compatible with alternative controls.