Amoebiasis is the general term applied to infection of man by Entamoeba Histolytica, the cause of amoebic dysentery. This infection may occur without clinical symptoms, or it may be characterised by diarrhoeal or dysenteric attacks, or by any other symptoms connected with the nervous or gastro- intestinal systems. The symptom complex known as amoebic dysentery is but one phase of Amoebiasis, and dysentery occurs in but a small proportion of infections with Entamoeba Histolytica. Although the condition is world -wide in distribution, the most severe symptoms and complications are most frequently observed in the Tropics. Durban, the town in which I reside, is situated on the south -east coast of the Union of South Africa. Its climate is humid, it has a native and Indian population of 150,000 most of whom live in the surrourding districts and whose personal hygiene and ideas of general sanitation are primitive in the extreme. A large proportion of this native community depend solely for a livelihood on market gardening, their produce being sold in the Borough Market. Another large proportion are domestic servants in homes and hotels. It is thus not surprising that the condition is the most wide spread disease encountered in Natal. As Honorary Physician at the King Edward VIII Hospital, with 120 beds in my charge, I have had exceptional opportunities of studying the disease and its many complications. In the last three years 382 cases have been treated in my wards. In the present thesis, I propose to summarise the irrportant work done on this subiect, and to give an account of my observations, especially with regard to the treatment of the conditions amongst the natives in Natal.