  I present a systematic study of all possible four leptons final states from
$\gamma\gamma$ collisions. It is given a detailed account of fermion masses
effects which are sizable since several collinear and $t$ channel enancements
occur. The effects of angular cuts on the final charged leptons are also
discussed. To perform the computation I have used the recently developed ALPHA
algorithm (and the resulting code) for the automatic computation of scattering
amplitudes.
