  In this review I focus on how massive stars in the disks of galaxies
determine the properties of the ionized, gaseous haloes of star-forming
galaxies. I first examine the ionization state of the halo, and conclude that
diluted radiation from massive stars, along with a possible secondary heating
source such as shocks, appears sufficient to explain the observations. I then
look at how single superbubbles evolve, as they must provide one of the main
mechanisms for transfer of mass and energy to the halo, as well as opening up
lines of sight for ionizing radiation to escape from the disk. Finally, I look
at the interactions of superbubbles, as they will rarely evolve in isolation,
and describe recent hydrodynamical and MHD simulations of the interstellar
medium shaped by multiple superbubbles.
