Methods for regioselective ring-opening polymerization of unsymmetrical cyclic diester monomers, polymers, which may be made by the methods, and uses of same. Monomers may include cyclic hydroxy-acid dimers, such as, for example, 3-methyl glycolide and the like. Polymerization initiators may include chiral metal alkoxide initiators, such as, for example, (SalBinam)Al-01Pr initiators and the like. Polymers may include polyesters, such as, for example, poly(lactic-co-glycolic acid) (PLGA) and the like, with 90% or greater regioselectivity for alternating ester units (e.g., glycolic unit-lactic unit (G—L) linkages). Polymers may be utilized for substained or targeted drug delivery vehicles, scaffolding for tissue engineering, bioabsorbable sutures, or the like.