New experimental approaches together with recent progress in spectroscopic technologies have given useful information to understand better the environmental fate of synthetic pyrethroids. The successive transformation of intermediate free radicals by using spin-trapping reagents and fluorophores enables their easier detection in aqueous photolysis. Chiral chromatographic analyses have shown stereo-selective metabolism of pyrethroids in soil. The knowledge on relevant enzymes in soil and plant being involved in hydrolysis, oxidation, and glucose conjugation of pyrethroids has been accumulated. Utilization of either iron-porphyrin with an oxidant or isolated leaf cells as model systems can give more information on metabolism of pyrethroids.