Shneider-Miles scattering (also referred to as collisional scattering or quasi-Rayleigh scattering) is the quasi-elastic scattering of electromagnetic radiation by charged particles in a small-scale medium with frequent particle collisions. Collisional scattering typically occurs in coherent microwave scattering of high neutral density, low ionization degree microplasmas such as atmospheric pressure laser-induced plasmas. Shneider-Miles scattering is characterized by a 90° phase shift between the incident and scattered waves and a scattering cross section proportional to the square of the incident driving frequency (). Scattered waves are emitted in a short dipole radiation pattern. The variable phase shift present in semi-collisional scattering regimes allows for determination of a plasma's collisional frequency through coherent microwave scattering.