Neutrinos are the only known elementary particles that are
Majorana fermion candidates, implying that they would be their own
antiparticles. The most sensitive and perhaps only practical probe the
Majorana nature of neutrinos is an extremely rate nuclear decay process,
the neutrinoless double beta decay. I will present the main techniques
to search for this decay, with focus on the GERDA experiment and the
future LEGEND. I will show current results and discuss the prospects to
probe the so-called inverted neutrino mass ordering scenario.