This work studies the mechanism and application of the novel diastereospecific ion-pairing polymerization (DIPP) effected by a catalyst system comprising chiral zirconocene bis(ester enolate) rac-(EBI)-Zr[OC((OPr)-Pr-i)=CMe2](2) [1, EBI = C2H4(Ind)(2)] and 2 equiv of Lewis acid Al(C6F5)(3). The 1/2Al(C6F5)(3) system effectively promotes DIPP of functionalized alkenes such as methyl methacrylate (MMA), producing polymers having various stereoregularities, including isotactic, syndiotactic, and isotactic-b-syndiotactic multiblock microstructures, depending on the [monomer]/[catalyst] ratio employed. Our detailed investigations into the polymerization characteristics and kinetics, elementary reactions, characterization and behavior of the isolated key intermediates, as well as temperature and Lewis acid effects have yielded a mechanism for the DIPP of MMA by the 1/2Al(C6F5)(3) system. This mechanism consists of four manifolds-isospecific, syndiospecific, anion-monomer exchange, and chain-transfer domains-and satisfactorily explains the formation of various polymer stereomicrostructures under given conditions. The most significant part of this overall mechanism is for the production of the isotactic-b-syndiotactic stereomultiblock structure, which is made possible by two pathways that can interconvert diastereospecific propagating manifolds: exchange between the coordinated anion and monomer as well as chain transfer. This unique polymerization technique has also been applied to the copolymerization of MMA with methacrylates having longer alkyl chains, leading to functionalized polymeric materials with tunable properties that are controlled by their stereomicrostructures and nature of the comonomer.