Current Toxicology Series Pesticides are used daily and internationally on a massive scale. They have conferred immense benefits to mankind by contributing significantly to improving health and nutrition, and to the economy in the form of cheaper food. This is mainly as a consequence of their use in crop protection, food preservation, and the control of insect vectors. However, this has sometimes been at a cost since improper and=or inappropriate usage has led to small- and large-scale poisoning incidents in humans, domestic animals, and wildlife, and resulted in significant adverse phytotoxic, ecotoxic, and general environmental adverse effects. Pesticides fall into numerous chemical classes, which havewidely differing biological activities and thus differing potential to produce adverse effects in living organisms, including humans. These considerations, coupled with the fact that, in addition to their use by highly trained agricultural and horticultural professionals, they are also generally available for use by less well trained or even untrained individuals, stresses the need for the control (regulation) of their release, use, and sale. This is further emphasized by the fact the pesticide industry is large, lucrative, and highly competitive.