  Electromagnetic corrections to the low-energy pi+ pi- -> pi0 pi0 scattering
amplitude at next-to-leading order in the chiral expansion are reviewed. Their
effects on the corresponding scattering lengths are estimated and compared to
the two-loop strong interaction contributions. Contribution to the proceedings
of the Eighth International Symposium on Meson-Nucleon Physics and the
Structure of the Nucleon, Zuoz, Engadine, Switzerland, August 15-21 1999.
