SUMMARY.— In the period 1955–69, 71 cases of porphyria have been diagnosed in South Australia, and include 4 cases of porphyria variegata and 34 cases of porphyria cutanea tarda. The general principles of treatment include the avoidance of alcohol, sunlight and trauma, and the establishment of a good dietary routine. Such principles lead to clinical remission in some cases, particularly in those who excrete less than 1 mg. of urinary porphyrins per day, but the majority also require active treatment and in South Australia sodium calciumedetate has been the treatment most used. We believe that it is possible to estimate the amount of chelation which will be necessary to obtain clinical remission: of the 28 treated patients with cutaneous porphyria whom we have been able to keep under observation, 27 obtained complete clinical remission following treatment with sodium calciumedetate.