Explore inelastic photon scattering in Josephson junctions at the Schmid transition in this 28-minute conference talk by Leonid Glazman at the Kavli Institute for Theoretical Physics. Delve into the physics of isolated small Josephson junctions, the effects of static polarization charge, and the impact of dissipative environments. Examine the transition from shunting resistors to Josephson junction arrays, and investigate the unique properties of transmons with multiple narrow bands. Analyze the new quantum impurity Hamiltonian and two mechanisms of inelastic photon scattering. Discover how the Schmid transition manifests in the differential inelastic cross-section and compare theoretical predictions with experimental results for the total inelastic cross-section. Conclude with insights into very long Josephson junction arrays, all within the context of transport and efficient energy conversion in quantum systems.