This chapter uses Hong Kong to illustrate the unique constitutional law challenges facing subnational jurisdictions, including that of dividing competences between the subnational and national authorities, of finding a mutually agreeable conflict resolution mechanism and of defining the place of the subnational constitution within the national constitutional order. As the only liberal, common law jurisdiction within a socialist party-state in the world, Hong Kong’s two decades of experience with China’s “one country, two systems” governing model illustrates how fraught the challenges facing a subnational constitution could be. Yet further reflection upon how Hong Kong can preserve its liberal constitutionalist status suggests creative solutions to those challenges.