The CDF experiment has developed several high p(t) b-jet
identification tools for the Run II physics program at the Tevatron.  Herein
we describe in detail one such b-tagging tool that exploits the
long-lifetime of the b quark by identifying decay vertices significantly
displaced from the primary interaction point.  The b-tag efficiency is
extracted from a b enriched data sample; the method is described, including
a discussion of the important systematic effects.  The data-driven
measurement of the false positive tag rate is also described, as well as an
explanation of how the per-jet false positive rate is used to predict the
background contribution to the selected sample.  Finally we conclude with a
discussion of issues that have proven critical for b-tagging at CDF and
should be given attention as we prepare b-tagging tools for LHC experiments.