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We discuss the impact of Population II and Globular Cluster (GCs) stars onthe derivation of the age of the Universe, and on the study of the formationand early evolution of galaxies, our own in particular. The long-standingproblem of the actual distance scale to Population II stars and GCs isaddressed, and a variety of different methods commonly used to derive distancesto Population II stars are briefly reviewed. Emphasis is given to thediscussion of distances and ages for GCs derived using Hipparcos parallaxes oflocal subdwarfs. Results obtained by different authors are slightly different,depending on different assumptions about metallicity scale, reddenings, andcorrections for undetected binaries. These and other uncertainties present inthe method are discussed. Finally, we outline progress expected in the nearfuture.Comment: Invited review article to appear in: `Post-Hipparcos Cosmic Candles',  A. Heck & F. Caputo (Eds), Kluwer Academic Publ., Dordrecht, in press. 22  pages including 3 tables and 2 postscript figures, uses Kluwer's crckapb.sty  LaTeX style file, enclose

Distances and Ages of Globular Clusters Using Hipparcos Parallaxes of Local Subdwarfs