Neutrino-less double beta decay is a process of great interest in the contemporary particle physics. The theoretical implications of it's observation are briefly reviewed, with some focus on the profound experimental implications of the uncertain knowledge of some parameters of the models that could explain the phenomenon. A comprehensive description of the experimental techniques, with the status of the corresponding most important experiments, is attempted. The results from presently active or recently finished experiments are compared with the sensitivity of near future projects in the framework of a multi-parameter analysis of the potential of each technology.