Rheological properties have been measured for solutions of polyesters containing quantities of inorganic and organic pigments. Complex behavior patterns were simplified by computing the effective volume fraction of dispersed solids, taking in account the thickness of polymer layers adsorbed on pigment surfaces. The dimension of interphases created by the adsorbed polymers was rationalized by applying principles of specific interaction between polymers and pigment surfaces. The parameters of specific interaction were obtained from inverse gas chromatographic data. Pigment sedimentation data were used to identify a range of specific interactions best suited to stabilize dispersions of the solids.