  Extremely rich populations of globular clusters, numbering ten thousand or
more, surround the central giant galaxies in rich clusters. I discuss some
recent spectroscopic and photometric observations of these rich globular
clusters populations. In very nearby galaxy clusters, the globular cluster
velocities can be used to trace the transition from the galaxy potential to the
larger cluster potential. Beyond cz \approx 3000 km/s, the globulars are too
faint for spectroscopic studies with even the largest telescopes and cease to
be useful dynamical tracers. However, the spatial distribution and size of the
globular population also contains information on the central mass distribution
of the cluster and can be measured out to cz > 20,000 km/s. Overall, the data
suggest that these rich globular cluster populations are comprised of normal,
old globulars, the majority of which were assembled in the cluster centers
before most of the stars in the cD galaxy were formed.
