Final talks to end 21 years of civil war in southern Sudan have resumed in the Kenyan capital, Nairobi, between the government and southern rebels.
Seven protocols have already been signed
Both sides have already agreed the main principles of a power-sharing deal.
These talks aim to sort out the finer details for a final settlement, including a permanent ceasefire.
However, the BBC's Adam Mynott in Nairobi reports there are fears that the crisis in Sudan's western Darfur region could derail the process.
A final peace settlement will tie together the seven protocols already signed by the government and the Sudan People's Liberation Movement (SPLM).
These deal with the share of power and wealth, the formation of a decentralised administration, and steps towards a referendum on succession for the south in six years time.
PRINCIPLES OF AGREEMENT
Unify the two sides into 39,000-strong force
The south will have autonomy for six years followed by referendum for secession
To be shared 50:50
To be split 70:30 in favour of the government in the central administration
To be split 55:45 in favour of the government in Abyei, Blue Nile State and the Nuba mountains
Islamic law to remain in the north
Khartoum's status to be decided by an elected assembly
But detailed planning will now begin into how these agreements in principle will be implemented, including how to pull troops back from the front line to form a unified army.
A lasting ceasefire also needs to be part of a comprehensive deal, as previously truces were agreed for two- or three-month periods.
Correspondents say it is a lengthy process and could take a long time.
Both parties have said they are committed to pursuing a successful outcome, despite delays on restarting the talks.
Sudanese President Omar al-Bashir has denied claims by SPLM leader John Garang that the Khartoum government is dragging its feet.
President Bashir said despite the negative stance of the SPLM, his government was determined to see the peace process through to its end.
Some two million people have died since the war in the broke out in 1983, when rebels in the Christian and animist south demanded autonomy from the Muslim north.