Why is English still the medium of education in Tanzanian secondary schools?

The paper looks for the reasons why Kiswahili has not been officially established as the medium of education in Tanzania although English has in practice largely ceased to perform that function. First, the language background is described and then the sociocultural and pedagogical arguments for a change to Kiswahili are examined. A comparison is made between French Immersion experiments in Canada and the use of English as a medium of instruction in Tanzania and significant differences between the two situations highlighted. The practical possibilities for the implementation of Kiswahili as the medium of instruction are discussed. Finally, it is argued that the real obstacle to change is powerful political interests which are best served by the retention of English.