  Recent work in low energy pion physics is reviewed. One of the exciting new
developments in this field is that simulations of QCD on a lattice now start
providing information about the low energy structure of the continuum theory,
for physical values of the quark masses. Although the various sources of
systematic error yet need to be explored more thoroughly, the results obtained
for the correlation function of the axial current with the quantum numbers of
the pion already have important implications for the effective Lagrangian of
QCD. The consequences for $\pi\pi$ scattering are discussed in some detail. The
second part of the report briefly reviews recent developments in the dispersion
theory of the scattering amplitude. One of the important results here is that
the position of the lowest resonances of QCD can now be determined in a model
independent manner and rather precisely. Beyond any doubt, the partial wave
with $I=\ell=0$ contains a pole on the second sheet, not far from the
threshold: the lowest resonance of QCD carries the quantum numbers of the
vacuum.
