Hyperbolic polaritons — hybrid light–matter quasiparticles emerging in extremely anisotropic media — have redefined the limits of nanoscale light manipulation. Their open isofrequency surfaces support high-momentum states and directional energy flow, enabling subdiffractional control that reaches the single-atom limit. Although initial progress was driven by artificial metamaterials, the discovery of natural hyperbolic materials spanning a dimensional hierarchy has shifted focus towards intrinsic, low-loss and highly tunable platforms. This Review establishes a transdimensional framework that unifies hyperbolic polaritons across 0D to 3D systems, encompassing shear, ghost and topological edge modes. We analyse the transition from descriptive exploration to a design-oriented paradigm, focusing on topological transitions and anomalous transport at interfaces for sophisticated wavefront engineering. Finally, we present an interdisciplinary framework for hyperbolic polaritons at the inter of materials science, physics, chemistry and information technology, outlining the strategic path towards integrated polaritonic circuits and quantum-chemical control.