  High-contrast scattering problems are special among classical wave systems as
they allow for strong wave focusing and localisation at low frequencies. We use
an asymptotic framework to develop a landscape theory for high-contrast systems
that resonate in a subwavelength regime. Our from-first-principles asymptotic
analysis yields a characterisation in terms of the generalised capacitance
matrix, giving a discrete approximation of the three-dimensional scattering
problem. We develop landscape theory for the generalised capacitance matrix and
use it to predict the positions of three-dimensional wave focusing and
localisation in random and non-periodic systems of subwavelength resonators.
