The experiments with the electromagnetic calorimeter TAPS using tagged photon beams focus on meson production from the free proton and from nucleons bound in nuclei. Following an introduction, results from the recent TAPS campaign at the tagged photon facility MAMI (Mainz) on double pion photo-production are presented. The observations using a proton target provide direct evidence for a \rho strength in the decay of the D₁₃ resonance. Furthermore, double pion production from nuclei is used as a tool to study in-medium modifications of the \pi \pi interaction which might indicate a partial restoration of chiral symmetry.

PACS numbers: 13.60.Le, 14.20.Gk, 25.20.Lj