Crop protection materials and techniques can increase productivity by preventing losses of yield or quality due to invading pests and by increasing the efficiency of men and machines. Spectacular advances have been made during the last 40 years in the availability of new highly active and relatively efficient chemicals which are reliable, safe, easy to use and cheap. Consequently, needs and opportunities for further new chemicals have slowed up in the last few years, while the costs of discovering and developing them have soared. Despite this agriculturally favourable situation, losses of productivity due to pests are higher than they need be. This is particularly so in after-harvest losses due to pest attacks which are still much too high in many crops and many countries. Increased productivity by better crop protection in the 1980s will demand better post-harvest protection of crops, more use of chemicals on an area basis, and spray programmes against a wider range of pest species. Early preventive usage should also increase, with less reliance on partial late cures. Most of the changing needs of individual farms in the 1980s can be met by the use of existing or forthcoming chemicals alone or in mixtures, or by special formulations or methods of use. As long as the chemical industry is not unduly hampered by irrational fears concerning the human environment, or long-term survival of agricultural soils, or the human race, it will continue to produce still more chemicals to combat existing and new agricultural problems, and should be encouraged to do so. One must, however, doubt whether non-chemical methods as we now know them will make more than a minor added contribution.