  Globular star clusters are extremely important astrophysical objects since
(1) they are prime laboratories for testing stellar evolution; (2) they are
``fossils'' from the epoch of galaxy formation, and thus important cosmological
tools; (3) they serve as test particles for studying the dynamics of the
Galaxy; (4) information on individual stars can provide constrains for stellar
dynamic models; (5) they are the largest aggregates in which all post Main
Sequence (MS) stars can be individually observed, and thus serve as fiducial
templates for all the studies of the integrated light from distant stellar
systems. In the framework of a long-term project devoted to a multi-band study
of stellar populations in Galactic Globular Clusters I present a set of recent
results of a systematic study of (1) the Red Giant Branch in the near-IR (J,K)
and in the optical bands; (2) the Horizontal Branch and Blue Stragglers stars
from mid- and far-UV observations obtained with HST.
