The system Pd(OAc)(2)/BQ/Co(acac)(3) (BQ = benzoquinone), in combination with tetrabutylammonium bromide (TBAB) as a surfactant agent and a chelating ligand such as 2,9-dimethyl-1,10-phenanthroline (dmphen) or 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (dmdpphen), is an efficient catalyst for the oxidative carbonylation of phenol to diphenyl carbonate (DPC), The best results have been obtained using the system Pd(OAc)(2)/BQ/Co(acac)(3)/dmphen = 1/30/8/5 (molar ratio) in which [Pd] = 10(-3) mol l(-1) and TBAB/Pd = 60/1. This system gives the maximum productivity of 700 mol DPC/mol Pd h at 135 degrees C and under P-tot = 60 atm (CO/O-2 = 10/1 molar ratio). The role of each component of the catalytic system is discussed and a catalytic cycle is proposed.