This article discusses Arab reactions to the development of a nuclear option in Israel. Various Arab positions on this problem are identified and then posited within the framework of the different Arab politico-strategic postures on the conflict with Israel. The main emphasis is put on the Egyptian position and here three strategies directed at deterring Israel from 'going nuclear' are described and analysed: the threat of preventive war; the threat that Egypt will 'go nuclear'; the search for outside assur ances. The article also analyses the effects of the development of the Israeli option on the conventional arms race between Israel and Egypt. Thus, the article is a case, study in the strategic behaviour of pairs of enemies of which one is a near-nuclear weapon State. Within this context there is also a discussion of whether the Israeli option had forced the Egyptian leadership to change her basic posture on the Arab- Israeli conflict. That this did not take place, proves that one of the tacit uses of the Israeli option, namely, to force by its very existence, Egypt to modify her position vis-à-vis Israel, has failed. Finally, the article establishes that there was no correla tion between the development of the Israeli option and crisis and war of 1967. This conclusion shows that at least in the Middle East and until 1967, the notion that the proliferation of nuclear options might destabilize parts of the international system, is not borne out.