  During the last two decades, the focus of star formation research has shifted
from understanding the collapse of a single dense core into a star to studying
the formation hundreds to thousands of stars in molecular clouds. In this
chapter, we overview recent observational and theoretical progress toward
understanding star formation on the scale of molecular clouds and complexes,
i.e the macrophysics of star formation. We begin with an overview of recent
surveys of young stellar objects (YSOs) in molecular clouds and embedded
clusters, and we outline an emerging picture of cluster formation. We then
discuss the role of turbulence to both support clouds and create dense,
gravitationally unstable structures, with an emphasis on the role of magnetic
fields (in the case of distributed stars) and feedback (in the case of
clusters) to slow turbulent decay and mediate the rate and density of star
formation. The discussion is followed by an overview of how gravity and
turbulence may produce observed scaling laws for the properties of molecular
clouds, stars and star clusters, and how the observed, low star formation rate
may result from self regulated star formation. We end with some concluding
remarks, including a number of questions to be addressed by future observations
and simulations.
