The fundamental Majorana or Dirac nature of neutrinos is still unknown.
Well-founded theoretical arguments suggest that neutrinos are Majorana particles, but the question must be resolved experimentally.
Neutrinoless double-beta decay is the most promising process for the revelation of the Majorana nature of neutrinos and the violation of the total lepton number.
In this mini workshop we will assess the theoretical status of neutrinoless double-beta decay, discuss its future prospects and how Snowmass can help.