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The electric ${\alpha}_{\pi}$ and magnetic ${\beta}_{\pi}$ charged pionCompton polarizabilities are of fundamental interest in the low-energy sectorof quantum chromodynamics (QCD). They characterize the induced dipole momentsof the pion during ${\gamma}{\pi}$ Compton scattering. Pion polarizabilitiesaffect the shape of the ${\gamma}{\pi}$ Compton scattering angulardistribution.The combination $({\alpha}_{\pi} - {\beta}_{\pi})$ was measuredby: (1) CERN COMPASS via ${\pi} Z \rightarrow {\pi} Z {\gamma}$ radiative pionPrimakoff scattering in the nuclear Coulomb field, (2) SLAC PEP Mark-II viatwo-photon production of pion pairs, ${\gamma} {\gamma} \rightarrow {\pi}^+{\pi}^-$, and (3) Mainz Microtron MAMI via radiative pion photoproduction fromthe proton, ${\gamma} p \rightarrow {\gamma} {\pi}^+ n$. Ongoing and plannedpion polarizability experiments (CERN COMPASS, BESIII at Beijing, JLab atNewport News) are also described. The Mark-II pion polarizability 95%confidence interval is approximately $0-11 \times 10^{-4} {fm}^{3}$, based on$({\alpha}_{\pi} - {\beta}_{\pi}) = (4.4 \pm 3.2) \times 10^{-4} {fm}^{3}$. TheMainz value $({\alpha}_{\pi} - {\beta}_{\pi}) = 11.6 \times 10^{-4} {fm}^{3}$is excluded on the basis of a dispersion relations calculation which uses theMainz value as input, and gives significantly too large ${\gamma} {\gamma}\rightarrow {\pi}^{0} {\pi}^{0}$ cross sections compared to DESY Crystal Balldata. To date, only the COMPASS polarizability measurement has acceptably smalluncertainties. Its value $({\alpha}_{\pi} - {\beta}_{\pi}) = (4.0 \pm 1.8)\times 10^{-4} {fm}^{3}$ agrees well with the two-loop ChPT prediction$({\alpha}_{\pi} - {\beta}_{\pi}) = (5.7 \pm 1.0) \times 10^{-4} {fm}^{3}$,thereby strengthening the identification of the pion with the Goldstone bosonof QCD.

Pion Polarizability 2022 Status Report