Polyurethane (PU) anionomers were prepared as aqueous dispersions and as solutions in tetrahydrofuran or absolute ethanol using dimethylol propionic acid (DMPA) as the stabilizing moiety, isophorone diisocyanate, polytetrahydrofuran, and cyclohexane dimethanol. The structure-property relationships were investigated for these PUs, cast as films, at similar and differing chain-extension levels. Comparisons were made with respect to the mechanical and viscoelastic properties and solvent resistance. Finally, the consequences of DMPA incorporation into the PU backbone were determined for two solvent-borne compositions of similar structure with and without DMPA. Dynamic mechanical thermal analysis, tensiometry, solvent spot tests, and swelling studies were employed for the characterization of the materials.