Scale Geometry is a research programme treating physical scale as a genuine geometric dimension. The core framework extends four-dimensional spacetime by a fifth coordinate representing scale position, with warp factor A(s) = −ln(cosh(ks)) — a single equation from which dark matter phenomenology, the cosmological constant hierarchy, the MOND acceleration scale a₀ = 1.2 × 10⁻¹⁰ m/s², and galaxy rotation curves across 175 SPARC galaxies (χ² = 1.08, zero free parameters) are derived. The Pöschl-Teller quantum potential admits exactly two bound states: ψ₀ (visible matter) and ψ₁ (dark matter), with the dark sector emerging from geometry rather than new particles. Related work includes E8-Scale Unification connecting discrete algebraic structure to continuous five-dimensional geometry, Time-Scale Unification demonstrating that time and scale are geometrically unified, biological applications (the A₀ Protocol for age reversal via Efficiency Selection), and independent convergence — three researchers in three countries arrived at the same founding postulate without knowledge of each other. This community welcomes original research on scale as a physical dimension, warped extra-dimensional frameworks, scale-dependent gravity, geometric approaches to dark matter and dark energy, and related unified theories.