Anion exchange membranes (AEMs) are essential components in clean energy technologies, yet their performance remains limited by an incomplete understanding of morphology–performance relationships and synthetic constraints. This dissertation addresses these challenges through a multi-faceted investigation into domain continuity and its effect on AEM properties. It begins with a critical review of current literature, emphasizing the importance of domain connectivity and the potential of block copolymers as model systems. Advanced characterization techniques and synthetic strategies are explored, laying the groundwork for more precise structure–property correlations.Next, the discussion shifts to the fundamental development of improved synthetic methods for the Pd-catalyzed living vinyl-addition polymerization of norbornenes, which is a technique particularly well-suited for the precise synthesis of AEM block copolymers. By systematically investigating polymerization conditions, this work provides mechanistic insights into factors influencing “livingness,” such as trace impurities commonly present in the monomers and catalyst, the stability of the activated Pd species, and the identity and stoichiometry of the activating salt. A novel experimental approach, termed “time-delay homopolymer chain extension experiments,” was developed to probe the behavior of active cationic Pd chain ends after full monomer conversion. Using this method, the shape and dispersity of the resulting molecular weight distributions serve as quantitative indicators of livingness. In addition, the mechanistic origins of early chain termination were investigated via 1H and 31P NMR spectroscopy study of a single-addition small-molecule active chain-end analog. Collectively, these studies yielded a set of optimized conditions that significantly enhance livingness and improved control over polymer architecture. The resulting insights establish a robust foundation for future synthetic efforts and expand the potential applications of functionalized polynorbornene materials. Finally, mechanistic insights into the vinyl-addition polymerization of norbornenes were applied to design well-defined block copolymer AEMs with tunable morphology, enabling a systematic investigation of the relationship between domain continuity and AEM performance. A series of ABC triblock terpolymers were synthesized via controlled vinyl-addition polymerization of norbornene monomers functionalized with alkyl, benzyl, or bromobutyl groups. The alkyl/benzyl block length ratio was systematically varied to tune morphology without significantly altering molecular weight or ion exchange capacity across the series. The resulting membranes exhibited either 2D-continuous lamellar or 3D-co-continuous network morphologies, with structural integrity maintained after cationic functionalization. Notably, AEMs with 3D-co-continuous domains showed superior performance, including enhanced dimensional stability and high hydroxide conductivities—reaching 84 mS/cm at 25 °C and 131 mS/cm at 80 °C. This work demonstrates that triblock terpolymer self-assembly can be harnessed to systematically investigate morphology–performance relationships and design highly conductive, durable AEMs for next-generation electrochemical applications.