Poly(ureidophthalimide)s decorated with hydrophilic side chains, that ensure soly. in aq. media, have been synthesized and characterized by UV/Vis and CD (CD) spectroscopy. Temp. and concn. dependent CD measurements in water have revealed an almost temp. and concentra-ion independent Cotton effect, indicative for a strong intramol. organization. Similar studies in THF demonstrate the dynamic nature of the secondary architecture, a characteristic of foldamers. In addn., the bisignated Cotton effect in water is opposite in sign to that in THF, suggestive for a solvent-dependent preference for one helical handedness. Mixing expts. prove the dominance of water in detg. the handedness of the helical architecture. The solvent allows for control over the helical architecture and thus governs the supramol. synthesis.