At the 7th annual SETAC World Congress, the PETA Science Consortium International presented a proposal for the introduction of the fish embryo toxicity test (FET; OECD Test Guideline 236) into the threshold approach for acute fish toxicity (OECD Guidance Document 126). Applying the threshold approach, in which an initial fish test is conducted at one concentration derived from test responses in Daphnia and algae and continued testing is triggered only if mortality is observed at this threshold concentration, can substantially reduce the number of fish used in the acute fish toxicity test. Using embryos instead of adult fish also provides a refinement to the threshold approach.