  In a recent Letter (PRL 88, 196404 (2002)), the effective g-factor and the
effective mass have been studied by Pudalov et al. in a dilute 2D electron
system in silicon. The authors contrast their data with the data obtained by
our group (Shashkin et al., PRL 87, 086801 (2001)) and claim that the spin
susceptibility "increases gradually with decreasing density", which "does not
support the occurrence of spontaneous spin polarization and divergence of
gm..." The purpose of this Comment is to show that all available experimental
data, including those of Pudalov et al., are consistent with each other and are
in favor of a spontaneous spin polarization and divergence of gm at a finite
electron density in this 2D system.
