Spherical micelles have been formed by mixing, in DMF, a poly(styrene)-block-poly(2-vinylpyridine)-blockpoly(ethylene oxide) (PS-block-P2VP-block-PEO) triblock copolymer with either poly(acrylic acid) (PAA) or a tapered triblock copolymer consisting of a PAA central block and PEO macromonomer-based outer blocks. Noncovalent interactions between PAA and P2VP result in the micellar core while the outer corona contains both PS and PEO chains. Segregation of the coronal chains is observed when the tapered copolymer is used.