  Recent seismic observations coming from acoustic and gravity modes clearly
show that the solar standard model has reached its limits and can no longer be
used to interpret satisfactorily seismic observations. In this paper, we
present a review of the non-standard processes that may be added to the solar
models in order to improve our understanding of the helioseismic data. We also
present some results obtained when applying ``non-standard'' stellar evolution
to the modelling of the Sun.
