  We summarize some recent results from our observational campaign to study the
central regions of spiral galaxies of late Hubble type (Scd - Sm). These
disk-dominated, bulgeless galaxies have an apparently uneventful merger
history. The evolution of their nuclei thus holds important constraints on the
mechanisms that are responsible for bulge formation and nuclear activity in
spiral galaxies. We discuss the structural properties, stellar populations, and
dynamical masses of the compact, luminous star cluster that is found in the
nuclei of most late-type spiral galaxies. Although preliminary, our results
strongly indicate that many galaxies of our sample experience repeated periods
of nuclear star formation. While the exact mechanism that leads to the required
high gas densities in the galaxy nucleus remains unclear, results from our
recent CO survey of late-type spirals demonstrate that in most cases, the
central kpc contains enough molecular gas to support repetitive nuclear
starbursts.
