Risk analysis methods as applied to the seven risk sectors have many commonalities but also many differences. An overriding feature is a firm foundation in drawing upon the results of scientific studies, the use of logic or deductive reasoning and the application of common sense in assessing risk and applying risk management measures. General principles that apply to risk analysis for aquaculture include application of the precautionary approach when dealing with uncertainty, transparency of the process, consistency in methodolody, use of stakeholder consultation, application of high level of stringency, use of minimal risk management interventions needed to achieve an acceptable level of risk, the concept of unacceptable risk and recognition that some "risky" actions cannot be managed and therefore should not be permitted under any circumstance, and the concept of equivalence where alternative risk management measures achieving the required level of protection are equally acceptable.