A descriptive account on pesticides has been presented in this book, including the elucidation of the current developments in chemical as well as botanical pesticides. Pesticides are regarded as potential molecules to fight against pests, weeds, diseases and insects in various systems like horticultural cropping system, agriculture as well as health management systems. Chemical pesticides are extremely efficient against the target organism. However, they also have toxic effects on numerous non-target species and rising environmental issues bring forth the topics of assessment of their toxicity and safety. The impacts of chemical pesticides on earthworms, fishes, advantageous microbes and natural enemies in agricultural ecosystems have been elucidated in this book. Moreover, the properties of pesticides to disturb the functioning of endocrine systems along with characteristics of non-conventional pesticide compounds have been descriptively discussed. The book also presents elaborative information regarding the current technology on use of biomarkers in pesticide analysis. Some of the plants having pesticidal dynamic compounds have also been covered. Interesting topics regarding the use of biotechnological strategies for insect pest management and a novel approach for recognition of larva in the field by LIRA classifier system have also been encompassed in this all-inclusive book.