Four linear and four star equimolar terpolymers based on non-ionic hydrophilic methoxy hexa(ethylene glycol) methacrylate, ionizable hydrophilic 2-(dimethylamino)ethyl methacrylate and neutral hydrophobic methyl methacrylate were synthesized using group transfer polymerization and investigated in aqueous dilute solutions. It was found that the (ABC)(n) multi-arm star terpolymers formed unimolecular micelles comprising three centrosymmetric compartments. The position of each compartment could be determined by the block sequence (ABC, ACB or BAC) at will. On the other hand, the ABC linear counterparts formed loose associates with very low aggregation numbers. It was shown that the polymer architecture (linear versus star) greatly affected the micellization phenomena of the terpolymers in selective media.