  The star forming process in the Milky Way is non-uniform in time and space.
The scale of star forming regions ranges from groups within a few pc to large
segments of spiral arms with linear dimension of order kpc. When many stars
form in a relatively small volume over a short duration, a localized starburst
ensues. The energetic impact of such a burst of star formation can severely
affect the dynamic structure of the gaseous disk. Stellar winds and supernova
explosions drive an expanding superbubble, whose size eventually exceeds the
scale height of the disk and thus drives a disk-wind blowing metal enriched gas
into the halo. We discuss the basic scenario of superbubble evolution,
emphasizing the associated gamma-ray line signatures. In particular, we discuss
nuclear line emission from 26Al and 60Fe in the Cygnus region.
