In this study, the synthesis of perfectly alternating poly(arylene ether ketone sulfone)'s (PAEKS) via their soluble poly(arylene ether ketimine sulfone) (PAEKetS) intermediates was described. In the first stage of this procedure a new bishalide monomer, 1,1'-bis(4-fluoro(n-benzohydroxylidene aniline)) sulfone (FBHAS) was synthesized. In the second stage, the polymerization of this monomer with various aromatic bisphenols to form the amorphous PAEKetS's and then the hydrolysis of the ketimine groups on the PAEKetS's backbones to ketones in mild acidic conditions in order to obtain perfectly alternating PAEKS's was conducted.