Almost all definitions of the precautionary principle emphasize the need for regulatory measures (actions) before it is established beyond doubt that an “intolerable" risk exists. Such measures are even more necessary the greater the depth of intervention is and the more irreversible the consequences may be. Risk mitigation in this case is not related to a reduction of risk, but rather to a policy that avoids irreversibility as much as possible. In the international literature, this approach is also popularly referred to as resilience strategy. In terms of assessment, it includes the need for conservative estimates in characterizing uncertainty and in terms of risk management it implies the need for ensuring opportunities for adapting to new situations, surprises and unexpected stress.