The precautionary principle was introduced into environmental politics in response to a perception that existing policies did not provide adequate protection to the environment. The most prominent formulation was adopted as Principle 15 of the Rio Declaration from the 1992 United Nations Conference on Environment and Development: "In order to protect the environment, the precautionary approach shall be widely applied by States according to their capabilities. Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation" (United Nations 1992). The principle has important implications to the interpretation of science and the regulation of technology, and is an expression of values in relation to the environment.

Terminology

It is important to distinguish between the precautionary principle, a precautionary approach, and precautionary action. The precautionary principle is a framework for thinking that...