  We examine self-consistent parameterizations of the high-mass stellar
population and resulting feedback, including mechanical, radiative, and
chemical feedback, as we understand them locally. To date, it appears that the
massive star population follows simple power-law clustering that extends down
to individual field OB stars, and the robust stellar IMF seems to have a
constant upper-mass limit. These properties result in specific patterns in the
HII region LF and ionization of the diffuse, warm ionized medium. The resulting
SNe generate superbubbles whose size distribution is also described by a simple
power law, and from which a galaxy's porosity parameter is easily derived. A
critical star-formation threshold can then be estimated, above which the escape
of Lyman continuum photons, hot gas, and nucleosynthetic products is predicted.
A first comparison with a large H-alpha sample of galaxies is broadly
consistent with this prediction, and suggests that ionizing photons likely
escapes from starburst galaxies. The superbubble size distribution also offers
a basis for a Simple Inhomogeneous Model for galactic chemical evolution, which
is especially relevant to metal-poor systems and instantaneous metallicity
distributions. This model offers an alternative interpretation of the Galactic
halo metallicity distribution and emphasizes the relative importance of
star-formation intensity, in addition to age, in a system's evolution. The
fraction of zero-metallicity, Population III stars is easily predicted for any
such model. We emphasize that all these phenomena can be modeled in a simple,
analytic framework over an extreme range in scale, offering powerful tools for
understanding the role of massive stars in the cosmos. (Abridged)
