  The power of the helicity formalism has been appreciated recently from its
application to the massless case, where plenty of formal aspects of multi-legs
amplitudes have been derived. However, in order to extend the formalism to the
realistic cases, such as the electroweak Standard Model and QCD with massive
quarks, some extra inputs are needed. We discuss first the formalism needed to
evaluate amplitudes expressed with the modern notation for massive fermions and
vectors based on a thorough treatment of Proca vector fields. Then, we present
some examples of elementary processes where it is shown how the formalism leads
to tremendous simplifications, these include 2-body decays $Z\to ff$, $h\to ff$
and $h\to W^{-}W^{+}$ as well as the 3-body decay $h\to V f'\bar{f}$.
