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An ESO Key programme dedicated to an Homogeneous Bright QSO Survey (HBQS) hasbeen completed. 327 QSOs (Mb<-23, 0.3<z<2.2) have been selected over 555 deg^2with 15<B<18.75. For B<16.4 the QSO surface density turns out to be a factor2.2 higher than what measured by the PG survey, corresponding to a surfacedensity of 0.013+/-.006 deg^{-2}. If the Edinburgh QSO Survey is included, anoverdensity of a factor 2.5 is observed, corresponding to a density of0.016+/-0.005 deg^{-2}. In order to derive the QSO optical luminosity function(LF) we used Monte Carlo simulations that take into account of the selectioncriteria, photometric errors and QSO spectral slope distribution. The LF can berepresented with a Pure Luminosity Evolution (L(z)\propto(1+z)^k) of a twopower law both for q_0=0.5 and q_0=0.1. For q_0=0.5 k=3.26, slower than theprevious Boyle's (1992) estimations of k=3.45. A flatter slope beta=-3.72 ofthe bright part of the LF is also required. The observed overdensity of brightQSOs is concentrated at z<0.6. It results that in the range 0.3<z<0.6 theluminosity function is flatter than observed at higher redshifts. In thisredshift range, for Mb<-25, 32 QSOs are observed instead of 19 expected fromour best-fit PLE model. This feature requires a luminosity dependent luminosityevolution in order to satisfactorily represent the data in the whole 0.3<z<2.2interval.Comment: Invited talk in "Wide Field Spectroscopy" (20-24 May 1996, Athens),  eds. M. Kontizas et al. 6 pages and 3 eps figures, LaTex file, uses epfs.sty  and crckapb.sty (included

The QSO Evolution Derived from the HBQS and Other Complete QSO Surveys