  I review recent results from numerical simulations on the structure and
dynamics of the ISM, and attempt to put together a coherent dynamical scenario.
In particular, I discuss results on 1) the spatial distribution of the gas
components, showing that reasonable agreement between simulations and
observations exists, but noting that in most models the components are simply
defined as temperature intervals, because distinct thermodynamic ``phases'' do
not arise; 2) some statistical issues of the physical fields, like the
dependence of the one-point statistics of the density field on the effective
equation of state of the gas, the poor correlation of magnetic strength with
density, the energy spectrum in weakly and highly compressible cases, and the
one point statistics of the velocity field; 3) the effects of spectroscopic
observation on distorting the physical structures and results from synthetic
observations of the simulations, and 4) several dynamical and thermodynamical
issues, such as the role of the thermal instability in forming and confining
clouds, the continuous, rather than abrupt, transition between ``phases'',
which in turn may be consequences of the dynamics rather than the agents
controlling it, the possibility of short time scales ($\sim $ a few Myr) for
molecular cloud formation, and the star-gas connection, mentioning that the
models generally exhibit self-propagating star and cluster formation, while the
stars may drive the medium- and small-scale gas motions, and that a ``star
formation instability'' may induce chaotic behavior of the star formation rate
locally. I conclude with a round-up view, and a discussion of the work needed
ahead.
