Neutrinoless Double β\beta-Decay: Status and Future

A brief summary of the status of neutrino masses, mixing and oscillations is presented. Neutrinoless double $\beta$-decay is considered. Predictions for the effective Majorana mass are reviewed. A possible test of the calculations of nuclear matrix elements of the $0\nu\beta\beta$-decay is proposed.Comment: A report at the International conference ``Non-Accelerator New Physics'' NANP05 Dubna, Russia, June 20-25, 200