The special section on Smarter Pest Control (16 August, p. 728) highlighted the threats that chemical pesticides pose to human health and the environment, and some of the smart alternatives, including genetically modified (GM) crops. However, an important and emerging technology against insect pests was overlooked: biological pesticides. Biopesticides are “derived from such natural materials as animals, plants, and bacteria” (1). They include microbial pesticides produced from fungi, protozoa, nematodes, baculoviruses, and bacteria (such as the widely used Bacillus thuringiensis, known as Bt). In the United States, there are about 400 registered biopesticide active ingredients and over 1250 products; there are many fewer in Europe (2). There has been substantial growth in biopesticides in recent years, especially in Asia, but they still comprise less than 4% of the global pesticides market (3). Market growth is undermined by the variable efficacy of some biopesticides, smaller market niches, and policy/regulatory barriers (2, 4). However, the potential for biopesticides is substantial, and many constraints can be overcome if, like other crop protection technologies, biopesticides also become smarter through research and innovation. Rather than treating biopesticides as synthetic chemicals, there is scope to develop and adopt novel production and delivery approaches that exploit their positive biological attributes (such as higher target specificity, capacity for secondary cycling, sublethal effects, genetic diversity, and transgenerational transmission) and minimize their negative ones (such as slower speed of kill and greater environmental sensitivity). GM technologies do have the potential to radically reduce pest damage, but their global-scale acceptability and adoption remain a long way off. In the meantime, biopesticides in general, and microbial pesticides in particular, offer the potential to reduce the chemical burden on the landscape while minimizing the evolution of resistance. In addition to delivering a more environment-friendly alternative to synthetic chemicals that is compatible with organic farming and integrated pest management programs, biopesticides may provide cheaper solutions for crop protection globally if policy and regulatory barriers can be minimized and harmonized (4). Kenneth Wilson1,*, Timothy G. Benton2, Robert I. Graham1, David Grzywacz3 1Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, UK. 2School of Biology, University of Leeds, Leeds, LS2 9JT, UK. 3Natural Resources Institute, University of Greenwich, Chatham Maritime, Kent, ME4 4TB, UK. ↵*Corresponding author: E-mail: email@example.com References ↵ U.S. Environmental Protection Agency, Pesticides: Regulating Pesticides (www.epa.gov/pesticides/biopesticides/whatarebiopesticides.htm). ↵ D. Chandler et al ., Philos. Trans. R. Soc. London Ser. B 366, 1987 (2011). Abstract/FREE Full Text ↵ T. Glare et al ., Trends Biotechnol. 30, 250 (2012). Services SFX pour l'INRACrossRefMedlineWeb of Science ↵ R. Ehlers , Regulation of Biological Control Agents (Springer, Dordrecht, Netherlands, 2011).