'Sextant' was the Allied two-part conference at Cairo in Egypt (22/26 November and 3/7 December 1943).

The main political leaders in attendance were President Franklin D. Roosevelt of the USA, Prime Minister Winston Churchill of the UK and Generalissimo Chiang Kai-shek of China, each of them accompanied by high-ranking government and military aides. The primary objectives of the conference were to plan the implementation of the agreements reached at the 'Quadrant' conference in Quebec, to agree the course of American, British and Chinese action against Japan, and (Roosevelt and Churchill) to formulate a post-war settlement of Europe. Premier Josef Stalin of the USSR refused to travel as far as Cairo at the time the Soviet army was involved in a major offensive, and the break during the 'Sextant' conference allowed Churchill and Roosevelt to travel with their aides to meet Stalin at Tehran for the 'Eureka' conference.

Little was decided at the 'Sextant' conference, for most major military problems required Stalin’s input, and the British and Americans could not agree on any genuine strategy for the prosecution of the war in South-East Asia given the intractability of Chiang and diverging US and British opinions of the theatre’s importance before the outcome of the European and Pacific campaigns had been decided. Moreover, the British tried to use the conference to urge the importance of the Mediterranean theatre while the Americans were adamant that 'Overlord' must remain the Allies' main effort in the European theatre, leading to a direct assault on Germany, its armies and its war-making potential.

Another problem to rear its head was the Allies' general shortage of amphibious capability, which meant that of the three amphibious operations envisaged before 'Overlord' only one could be undertaken: these three were 'Shingle' against Anzio in Italy, 'Hercules' against Rhodes in the Aegean, and 'Buccaneer' against the Andaman islands group in the Indian Ocean as a stepping stone to Malaya and the Netherlands East Indies.

The main decisions reached during the 'Sextant' conference were a dedicated affirmation for the simultaneous (or nearly simultaneous) launch of 'Overlord' and 'Anvil' as a priority over all other European operations (a decision conveyed to Stalin at the 'Eureka' conference), the use of two US divisions for 'Anvil' followed by 10 more US divisions from the USA, the prosecution of the Italian campaign for the capture of Rome and an advance to the line of Pisa and Rimini, and the retention of 68 tank landing ships in the Mediterranean until 15 January (six weeks later than originally planned). This last meant the cancellation of 'Buccaneer', much to the chagrin of Roosevelt, who had promised Chiang that the operation would proceed, the implementation of 'Shingle' and the possible undertaking of 'Hercules' if other considerations could be achieved.

Another decision was the approval of the 'Overall Plan for the Defeat of Japan', which called for a continued two-part US advance against the Japanese by separate but closely co-ordinated army- and navy-led forces. Within this scheme General Douglas MacArthur’s South-West Pacific Area command was to continue its advance to the north-west along the coast of New Guinea, and Admiral Chester W. Nimitz’s Pacific Ocean Areas command was to advance to the Marshall islands group in January 1944, the Caroline islands group (including Truk) in July, and the Mariana islands group in October. Neither the US Army nor the US Navy was given overall strategic responsibility for the Pacific theatre, but the US Navy was ordered to deploy its ship assets 'to support successive operations along each axis'. In the event of disputes between the two parties, the decision on resources allocation was to be taken by giving 'due weight to the fact that operations in the Central Pacific promise, at this time, a more rapid advance toward Japan and her vital lines of communications; the earlier acquisition of strategic bases closer to the Japanese homeland; and, of greatest importance, are more likely to precipitate a decisive engagement with the Japanese fleet'.

The press release after the end of the first part of the 'Sextant' conference revealed the Allies' intention to divide the Japanese empire after the defeat of Japan. The document said that all territory seized by Japan since World War I (and including Formosa and Manchuria) would be returned, and that all Japanese land seizures in China would also be handed back to China. It also called for Korea to become an independent state. The three main clauses of this Cairo Declaration were that 'Japan be stripped of all the islands in the Pacific which she has seized or occupied since the beginning of the First World War in 1914', 'all the territories Japan has stolen from the Chinese, such as Manchuria, Formosa, and the Pescadores, shall be restored to the Republic of China', and 'in due course Korea shall become free and independent'.

The second half of the conference was attended by Mustafa Ismet İnönü, the president of Turkey, whose greatest success in a long military and political career was, possibly, keeping Turkey out of World War II.