The miscibility of blends of bisphenol-A based poly(arylene ether)s and poly(hydroxy ether)s has been investigated. The blends were prepared from solutions in chloroform and analyzed using calorimetric, thermal and spectroscopic methods. Blends of poly(arylene ether phosphine oxide) [PEPO] and bisphenol A polyhydroxy ether (phenoxy resin) were miscible, whereas blends of the phenoxy resin with poly(arylene ether ketone) [PEK] and with poly(arylene ether sulfone) [PSF] were immiscible. FTIR studies suggested that strong specific interactions, particularly hydrogen bonding between the P=O functional groups of PEPO and pendant -OH groups of the phenoxy resin, promoted miscibility in the PEPO/Phenoxy system. Blends of a 50/50 PSF/PEPO copolymer and Phenoxy exhibited properties expected of a single phase, suggestive of a miscible blend. Miscible poly(arylene ether) blends with the model polymer matrix - Phenoxy, have potential use as interphase materials in carbon fiber epoxy (or vinyl ester) matrix composites.