The distribution of massive stars in space and in
stellar mass are fundamental parameters that define them as a
population. What are the clustering properties of massive stars,
and what is the relation of those in the field to those in clusters?
What is their initial mass function, and in particular, the upper-
mass limit? The high-mass stellar population drives feedback effects
that are fundamental to galaxy evolution. What feedback effects
derive from the nature of the population? I will present work
addressing these issues, from which a more comprehensive picture
is emerging of massive stars as a population.