  A brief review is given concerning the status of the theoretical work on
nucleon spectral functions. A recent concern about the validity of the concept
of spectroscopic factors as deduced from (e,e'p) reactions at higher Q^2, is
discussed in some detail. The consequences of the observed spectral strength
are then considered in the context of nuclear saturation. It is argued that
short-range correlations are mainly responsible for the actual value of the
observed charge density in 208Pb and by extension for the empirical value of
the saturation density of nuclear matter. This observation combined with the
general understanding of the spectroscopic strength suggests that a renewed
study of nuclear matter, emphasizing the self-consistent determination of the
spectral strength due to short-range and tensor correlations, may shed light on
the perennial nuclear saturation problem. First results using such a scheme are
presented.
