Abstract The scientific discourse on risk that has been carried out for many years now has drawn attention to the fact that the conventional concept of risk based on the product of probability and extent of damage is not applicable to the risk of modern technologies (e.g. genetic knowledge society, uncertainty, global risks, risk communication, decision, expert, contingencyengineering). This is so because we are dealing with hypothetical dangers for which neither the possible extent of damage nor the probability of the occurrence of accidents may be calculated in any exact sense in advance. In the form of technically and ecologically induced risks uncertainty – in relation to the consequences – has become a basic contentious problem of modern society viewed as a knowledge society. Decisions with regard to uncertainty can only be made as part of social processes or hypothetical situations. Processing uncertainty, ambiguity and impossibility is the most distinctive characteristic of future-oriented decision making and risk communication.