This paper was written to be offered to the Council of the Royal United Service Institution, London. Acting on the advice of Major-General Sir Charles MacGregor, K.C.B., C.S.I., C.I.E. I resolved to make it less public and to issue it only to those who have studied or who are concerned with the problem of the defence of India and of the Empire, in the hope that the opinions put forward may be criticised and the requirements of an imperial military policy arrived at. In order not to lengthen the paper too greatly, many important points have been but touched upon; it is proposed shortly to elucidate them further by notes on Imperial Strategical Communications.