Polybrominated diphenyl ethers (PBDEs) are ubiquitous environmental pollutants due to theirpersistent character and extensive use as additive flame retardants. In order to assess theirbiological effects, fate, environmental concentrations and other parameters related to riskassessment, authentic PBDE congers are needed for research purposes. In the present work anew general method for the preparation of individual PBDE congeners is presented. Themethodology used is based on recent advances in unsymmetrical diaryliodonium saltsynthesis as well as advances in O-arylation of phenols with these types of salts. Accordingly,three brominated diphenyliodonium triflates were prepared i.e. phenyl(2,4,5-tribromophenyl)iodonium triflate, phenyl(2,4,6-tribromophenyl)iodonium triflate andphenyl(2,3,4,6-tetrabromophenyl)iodonium triflate from 1,2,4-tribromo-5-iodobenzene, 1,3,5-tribromo-2-iodobenzene and 1,2,3,5-tetrabromo-4-iodobenzene, respectively. Yields indiaryliodonium salt syntheses ranged from 69-96%. These salts were further used to O-arylatevarious brominated phenols giving individual tetra- to octa-BDE congeners in yields rangingfrom 64-98%. The O-arylation method used was given after a minor optimisation study, regarding reaction time and temperature, which is reported herein. In addition, this O-arylationmethod was also used with two brominated methoxyphenols in the syntheses of twomethoxylated PBDEs.