A heteroarm star block copolymer made from seven polystyrene and seven poly(2-vinylpyridine) armswas grafted onto a solid substrate to fabricate a responsive polymer surface consisting of a densely packedmonolayer of copolymer molecules. The grafted layer demonstrates a two-level hierarchical response uponexternal stimuli combining core−shell transitions of single stars with cooperative transitions of theinteracting arms between “dimple” and “ripple” morphologies of the monolayer. The response allows forthe switching of the surface properties upon changing solvent selectivity or pH of the aqueous environment.