Substantive progress was scarce in the previous three rounds over nearly two years, while disagreements, fresh demands and pitfalls bred complications.
Following are key points surrounding the six-nation talks.
Give and take
The basic premise of the talks is for North Korea to dismantle all nuclear weapons programmes in a verifiable and irreversible manner in exchange for much-needed aid for its moribund economy and security guarantees.
China hosted three rounds of talks beginning in August 2003 with North and South Korea, the United States, Japan and Russia. It was not until the third round in June 2004 that substantive proposals were made. No discussions on the proposals have followed so far.
What North Korea wants
The North has sought energy aid, its removal from the US list of state sponsors of terrorism and lifting of all sanctions against it.
It has said it wants to see those moves in return for a freeze of its nuclear programmes, before it begins dismantling them.
Since March this year, the North has demanded that the six-party process be turned into disarmament talks that would also discuss US nuclear weapons it says are deployed in South Korea. Washington denies the existence of such weapons.
Pyongyang has also repeated calls for a peace treaty with the United States.
Washington wants to see the North begin dismantling all nuclear programmes, including one based on uranium enrichment technology, within three months of freezing them. It has not offered to be directly part of an energy aid package.
Tokyo says the issue of Japanese citizens abducted by the North Koreans decades ago should be raised at the Beijing talks. Washington sees the need to include North Korea's record of human rights abuse on the table. Seoul has tried to keep this coming talks session focused on the North's nuclear arms.
All the parties, including North Korea, say they are prepared to work for substantive progress.
Another breakdown could mean the end of the six-party process and renewed US calls to take the issue to the UN Security Council, which could impose sanctions.
(Sources: South Korean Foreign Ministry, Reuters and other