To protect the continued use of biopesticides, the Environmental Protection Agency is requiring companies developing transgenic crops (see genetic engineering) to submit and implement pest resistance management (PRM) plans as a requirement of product registration. If they are exposed to a toxin excessively, most insect populations can develop resistance, making pest control products less effective. With new biopesticide technologies comes the concern that pests will rapidly develop resistance to natural insecticides. A resistance management plan is intended to sustain the useful life of transgenic technology.