has further broadened controversial though this subject and indeed the results of amygdaloidotomy may be. lt was Jinnai in 1963 who first published his work on the control of intractable epilepsy by interruption of conduction pathways of the epileptic discharge using stereotactic lesions in the field of Forel. This was followed by lesions in the thalamus by Mullen in 1967, and by capsular lesions by Bertrand in 1970 and myself in 1971. In the macroscopic form this was carried out by section of the inter- hemispheric cerebral connections by open operation by Vogel in 1969. This has been an important contribution to knowledge of the basic mechanisms of the propagation of the epileptic discharge and to our understanding of brain function but I would look to stereotactic techniques for the greater development potential. There are, of course, limitations. Bilateral lesions of effective size are difficult to achieve without side effects, particularly in respect of speech (notably dysarthria) and yet are essential if intractable epilepsy is to be con- trolled in severity and frequency. Increased accuracy of target siting and control of the size of lesion are not the whole answer for inevi- tably there are areas where important neuronal circuits are very crowded. But we should not underestimate the contribution of surgery. Increasingly the medical therapy of epilepsy is under scrutiny.