The pest management industry does not have adequate financial incentives to develop the required data to register pest management tools with government authorities on fruit, vegetables, herbs, spices, nursery crops, landscape plants, flowers, turfgrass, and other specialty crops. Growers of these crops, collectively called minor crops, need pest control tools to be able to sustain production. The Interregional Research Project Number Four (IR-4) was established in 1963 by the U.S. Department of Agriculture to assist growers of minor crops by providing a mechanism to allow growers of these crops to have access to safe and effective pest management tools. Working with research, industrial and extension personnel at the state land-grant institutions and researchers at USDA, Agricultural Research Service, IR-4 develops the appropriate data to support registration of insecticides, fungicides, herbicides and plant growth regulators. Many of the uses of plant growth regulators in current use were developed with oversight provided by IR-4. There are many promising new plant growth regulators and/or uses in the commercial development pipeline and it is anticipated that assistance from IR-4 will be needed to support registration of these new materials on minor crops.