  The nitrogen and oxygen abundances in the warm ionized gas of low-mass,
metal-poor galaxies appear surprisingly homogeneous considering the prevalence
of large HII regions, which contain hundreds of massive stars. Of the six
galaxies with extensive optical spectroscopy, only the largest and most
metal-rich, the LMC, shows evidence for a chemical gradient akin to those
commonly seen in spirals. Furthermore, no significant localized chemical
fluctuations are found in the vicinity of young star clusters, despite large
expected chemical yields of massive stars. An ad-hoc fine-tuning of the
release, dispersal and mixing rates could give rise to the observed
homogeneity, but a more probable explanation is that fresh ejecta reside in a
hard-to-observe hot or cold phase. In any case, the observations indicate that
heavy elements which have already mixed with the warm interstellar medium are
homogeneously dispersed. Mixing of fresh ejecta with the surrounding warm ISM
apparently requires longer than the lifetimes of typical HII regions (>10^7
yrs). The lack of observed localized chemical enrichments is consistent with a
scenario whereby freshly-synthesized metals are expelled into the halos of
galaxies in a hot, 10^6 K phase by supernova-driven winds before they cool and
``rain'' back down upon the galaxy, creating gradual enrichments on spatial
scales >1 kpc.
