  In comparison with other well studied star formation regions, Taurus is
unusual in several respects. (i) Its stellar initial mass function (IMF) peaks
at relatively high mass ($\sim 0.8 M_\odot$), but contains very few stars much
more massive than $1 M_\odot$, and is relatively deficient in brown dwarfs.
(ii) It has a higher binary fraction, particularly at large separations. (iii)
Its core mass function is strongly peaked at a few $M_\odot$, and the cores
have extended envelopes and relatively low levels of turbulence.
  We present here the results of an ensemble of hydrodynamic simulations which
suggest that the unusual stellar IMF in Taurus is a direct consequence of the
unusual properties of the cores there. By following the collapse and
fragmentation of cores having properties typical of Taurus, we find that
roughly 50% of the objects formed in a core, predominantly the low-mass ones,
are ejected from the core to form a population of low-mass stars and brown
dwarfs with a flat mass function. The remaining objects form multiple systems
within the core, accreting until their masses approach $1 M_\odot$; this
produces a population of intermediate-mass stars whose mass function peaks at
$\sim 0.8 M_\odot$. Together these two populations reproduce the IMF in Taurus
very well. This demonstrates, for the first time, a direct causal link between
the core mass function and the stellar IMF in a star formation region.
