The sciences analyzing and describing risks are relatively new and developing, and the associated terminologies are developing as well. This has led to ambiguity in the use of terms, both between different risk sciences and between the different parties involved in risk debates. Only recently, major vocabularies have been compiled by authoritative agencies. Some of these vocabularies are examined and explained based on a division into fundamental and action oriented risk terms. Fundamental terms are associated with description and characterization of the chemical, biological and physical processes leading from risk source(s) to possible consequences/effects. The approach to these terms is based on a cause-effect skeleton. The action oriented terms cover administrative, scientific, sociological, etc. processes associated with the work of identifying, characterizing, regulating and communicating risks in the society, and their internal connection and iterative character have been illustrated. Focus is laid on engineering and toxicological risks, but to some extent, the thoughts presented may be extrapolated to other areas. Differences in applied terminology probably cannot be eliminated, but they can be identified and clarified for better understanding. With the present paper, the authors hope to contribute to reducing the probability of derailing risk discussions from the risk issue itself. (C) 2003 Elsevier B.V. All rights reserved.