  We present a class of L\'evy processes for modelling financial market
fluctuations: Bilateral Gamma processes. Our starting point is to explore the
properties of bilateral Gamma distributions, and then we turn to their
associated L\'evy processes. We treat exponential L\'evy stock models with an
underlying bilateral Gamma process as well as term structure models driven by
bilateral Gamma processes and apply our results to a set of real financial data
(DAX 1996-1998).
