Observation of neutrino-less double beta-decay would demonstrate that the neutrino and anti-neutrino are identical. This decay mode would be prohibited if the neutrino has zero mass but the discovery of neutrino oscillations, demonstrating a non-zero mass, has strongly motivated new experimental searches. While knowledge of mass and phases is incomplete, oscillation results have provided a target range of desired search sensitivity, about a factor of about 100 greater than the current experimental limits. I will present a personal perspective on current experimental aspirations in the international context. A 'discovery class' experiment requires a ton-scale active mass and background levels reduced by more than two orders of magnitude. Is this technically possible? For the US, an opportunity appears to exist in the use of gas-phase xenon with development of new methods for background reduction, as pursued within the NEXT collaboration. The elusive neutrino may yet provide more surprises, even insight as to why there is something, rather than nothing.
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