The International Commission on Radiological Protection (ICRP) is now reviewing its recommendations with a view to publishing their revision in 2005. The last set of recommendations issued by the ICRP has caused some concern to neutron dosimetrists. This paper attempts to explain these concerns. Technological developments make it likely that exposure to high-linear energy transfer (LET) radiations will increase in the future. It is in the area of the dosimetry of high-LET radiations, particularly neutrons, where some experts feel that ICRP recommendations have been unclear. This paper discusses the process of setting protection limits in toxicology and its application to radiation protection. The development of radiation protection quantities and models is described, and the problems found with effective dose described. Suggestions for improvements are made that would enable effective dose to serve in two modes--both as a limiting quantity and also as the measurable (operational) quantity required by dosimetrists.