The story in this book is about a biologically potent new ligand monobutylphthalate which has been synthesized by the ring opening reaction of phthalic anhydride with butanol using dean stalk trap. Eight transition metal complexes have been synthesized from this novel ligand in 1:1 and 2:1 stoichiometry. The geometry of the resulting complexes was proposed through IR spectroscopy. Ligand and complexes were than subjected to various bacteria and fungi in order to establish their biological activity. Results reveal that the ligand and complexes exhibit significant to promising activity against all type of bacteria and fungi. This monograph is equally beneficial for both beginners and also ideal for experts