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Well-defined diblock copolymers {PS- b-P(ϵ-CL)} and triblock terpolymers {PS- b-PI- b-P(ϵ-CL), PI- b-PS- b-P(ϵ-CL)} of polystyrene, PS, poly(ϵ-caprolactone), P(ϵ-CL), and polyisoprene, PI, were synthesized using CpTiCl 2(OP) (P = PS, PS- b-PI, or PI- b-PS) as macroinitiator. Graft copolymers having polybutadiene, PBd, backbone and poly( n-hexyl isocyanate), PHIC, or P(ϵ-CL) branches {PBd- g-PHIC and PBd- g-P(ϵ-CL)} as well as block−graft terpolymers {PS- b-(PI- g-PHIC), PS- b-[PI- g-P(ϵ-CL)]} were also synthesized by performing hydroboration/oxidation reactions on the polydiene backbone and by transforming the introduced hydroxyl groups to initiation sites by reaction with CpTiCl 3. Finally, PS(PHIC) 2and PS[P(ϵ-CL)] 23-miktoarm star copolymers were synthesized using a heterofunctional initiator bearing one initiation site for atom transfer radical polymerization and two for titanium-mediated coordination polymerization. All intermediates and final products were characterized by size exclusion chromatography, equipped with refractive index and light scattering detectors, membrane osmometry, and 1H NMR spectroscopy. [ABSTRACT FROM AUTHOR]