Sanzples consistiny of the whole above-ground part of the oilseed rape plant (Brassica napus L ), were taken every 2 weeksfrom before stem extension to nzuturity. The plants were .reparated into vegetative tis.sue,,floral tissue, pods und seeds (vvhen these components appeared), and the indii)idual glucosinohtes present were quanrtfied by high performance liquid chromatographj.. A high glucosinolate varier?' (Rufal) and a low glucosinolate variety (Cobra) were compared. The effect qf sulphur (32 kg ha-elenzental sulphur upplied at the beginning of stem extension) on the various parts of the plant wus investigated. Total ylucosinolate concentration in ull plant parts was higher in Rafal than in Cobra. Glucosinolate concentrution in the vegetution declined over time, most tioticcablj~ rvhm the ,flowers and seeds were procluced, und glurosinolare concentration of the pods also ,fell as that of the seeds rose. It is suggested that there may have been some redistribution of ylucosinolutes or glucosinolate precursors u3ithin the plant us maturity approached. Changes occurred in the proportions that individual glucosinolates contributed to the total ylucosinolate content, and this may he relevant to plantlpathogen relationships. Sulphur application increased the glucosinolate concentrution of' the vegetative tissue by nzid April and also increased the glucosinolate concentration of'the,floicws. It is suggested that this could affect the plant I s resist an ce to disease .