The development by ruminants of strong conditioned flavour aversions (CFAs) to foods associated with the administration of LiCl (an artificial toxin) has demonstrated their potential to avoid feeds that cause negative postingestive consequences (Provenza, 1995). Weaker CFAs are formed when they ingest foods with the detrimental secondary plant compound, oxalic acid (Kyriazakis et al. 1997). Moreover, animals may exhibit conditioned preferences (CFPs) for foods supplying appropriate amounts of nutrients such as nitrogen (Provenza, 1995). In this study we tested whether a continuum exists in the formation of CFAs and CFPs to foods that are associated with increasing availability of sulphur (S) in crossbred ewes.