The recognition of sulphur deficiency during the last few years over large areas of the South Island may be said to have originated in trials by Lobb (1953, 1954). The implications of earlier work by Doak (1929) and others had not been fully appreciated. After seeing some of the responses obtained by Lobb in North Otago, we at Lincoln decided to examine the nature of sulphur responses in Canterbury. After some initial experiments on rape (Walker, Adams, and Orchiston, 1954), where sulphur was shown to be of slight importance, emphasis was shifted to the tussock country in the Canterbury foothills (Walker, Adams, and Orchiston, 1955 and unpublished data). This paper will summarise most of our work.