The polarity characteristics of methyl/phenyl OV type GLC stationary phases (OV-101, -3, -7, -11, -17, -22, -25) and low molecular weight analogues (hexamethyldlslloxane, octamethyltrislloxane, decamethyltetraslloxane, and bls(trlmethylsilyl)methane) are examined via the solvatochromic comparison method. As expected, the differential polarity of the OV liquids Is due In large measure to differential polarizability effects and Is well correlated with a reaction field based model. In addition, a nearly constant low level of hydrogen bonding acceptor strength Is observed. The presence of measurable hydrogen bonding acceptance In these liquids has Important implications to the Interpretation of retention of strong hydrogen bond donors on these stationary phases In GLC. Likewise, the Interaction of strong hydrogen bonding solutes with the slloxane backbone of silica gel In liquid chromatography may be a significant, and generally neglected, effect. It appears the detailed analysis of the origin of retention of strong hydrogen bond donors on these materials may warrant reexamination.