In this chapter, we want to deal with environmental risks, environmental hazards, and environmental disasters. Risks and hazards lurk in the entire environment, the natural, the technical, and also the social environment. However, we will not address the latter at this point. In this chapter, we primarily deal with natural and technical environmental risks, environmental hazards, and environmental disasters. In doing so, we highlight the psychological differences that exist between both types of risks. Risks are per se a matter of uncertainty and probability. Therefore, we first address the implications of uncertainty on experience, judgment, and action, and finally discuss the experience and behavior of people during a disaster and afterwards. But first, the question arises as to what is meant by the terms risk, hazard, and disaster.