[en] The paper discusses the theory and experiments on controlling the probability of spontaneous gamma decay and lifetime of radioactive and excited nuclei. The phenomenon of nuclear decay controlling is a result of interaction of these nuclei with zero-energy electromagnetic modes, which in turn interact with the controlling resonant screen. The most significant influence on the nucleus spontaneous decay process will be realized in case when these modes occur to be mutually synchronized. In this case the radiative lifetime may be increased by many orders of magnitude. The phenomenon of gamma decay controlling was experimentally studied by Moessbauer spectroscopy. In experiments with gamma sources Co⁵⁷(Fe^57*) or Sn^119m and absorbers Fe⁵⁷ or Sn¹¹⁹ we have discovered the change (increase) of Moessbauer radiative lifetime of excited nucleus by 20 100 % and total lifetime (including non-Moessbauer radiation and electron conversion) by 0.6-2.0 %. The creation of optimal systems for controlled utilization, transportation, treatment and storage of gamma-radioactive waste by this method of controlled gamma decay is also discussed. (author)