A series of polyphosphonates were synthesized by base promoted liquid-vapor interfacial polycondensation of various alkyl (aryl) phosphonic dichlorides (methylphosphonic dichloride (MPD), cyclohexylphosphonic dichloride (CPD) and phenylphosphonic dichloride (PPD)) with different bisphenols (hydroquinone (HQ), bisphenol A (BA), 4,4' - biphenol (BP), 1,5-naphtalenediol (ND) and 4,4' - sulfonyldiphenol (SD)). The polyphosphonates were characterized by infrared (IR) and proton magnetic resonance (H-1-NMR) spectroscopy. Yields in the range of 20-80% and Mn of similar to8500-35000 were obtained. DSC measurements show Tg in the range 95degrees-148degreesC. These polymers are soluble in solvents such as N,N-dimethylformamide, tetrahydrofuran and chloroform. Polyphosphonates were stable up 240degrees-300degreesC in air atmosphere.