This volume examines major enzymatic processes involved in pesticide transformation such as hydrolysis, oxidative and reductive metabolism, conjugation and dehalogenation in plants and microbes in the area of xenobiotic metabolism. The molecular biology, enzymology, and regulation of these processes are presented, as well as the use of in vitro cultures of microorganisms and plant tissues to elucidate metabolic pathways of pesticide transformation. Where possible the similarities and differences between enzymes associated with pesticide degradation pathways in microbes and plants are discusses. The text highlights the potential for biorational pesticide design and the limitations of developing synergistic pest control strategies for integrated weed management. The practical implications of plant and microbial biotechnology to manipulate these metabolic transformations to enhance crop production and pest management are also discussed.