There is a growing gap in the market for environmentally friendly, selective insecticides and biocides for use in the production of food crops. This has been driven by tightening regulations on chemical products, as well as customer demand for no-chemical residue food products. As insect hormone neuropeptides govern almost all aspects of insect physiology and survival, neuropeptide-based insecticides may thus provide selective and rational bioinsecticides for plant protection, including additional routes for IPM. This chapter sets out to first address the issues involved with the control of insect pests, and then goes on to fully review the potential of peptide-based biopesticides. Neuropeptide profiling, neuropeptide families, peptide modifications and synthetic chemistry and validation approaches are covered, and the assessment of peptide effects on insects is also included. The chapter summary looks at how such research can contribute to sustainable agriculture.