The Forum is a political grouping of 16 independent and self-governing states.
The summit is being held under the banner "Small and Far: Challenges for Growth".
The meeting begins with the Smaller Islands States Leaders meeting, while all of the island countries will be represented at Thursday's meeting of the group of African Caribbean and Pacific group of nations.
The summit proper gets underway on Thursday with the plenary session set for Friday and the leaders retreat scheduled for Saturday.
West Papua an issue
The Forum's failure to undertake a promised fact-finding mission to West Papua.
Islands Business reports the Secretary General of the Pacific Islands Forum, Dame Meg Taylor, saying West Papua is a sensitive issue for some Pacific governments, but one that needs to be debated.
She told the magazine that it is an issue that needs to be pursued and it's not going to go away.
Dame Meg said the bigger countries in the region like Australia and New Zealand realise that this issue is just not going to go to sleep - and it shouldn't go to sleep, because it is very important for Pacific.
At last year's Forum in Port Moresby a decision was reached to have the chair, PNG Prime Minister Peter O'Neill, propose a factfinding mission to Indonesia, but Dame Meg said Jakarta has indicated it would not welcome a Forum delegation, and was uncomfortable with the term "fact-finding."
Meanwhile Nauru and Tuvalu have joined the Pacific Coalition on West Papua, voicing their concerns over human rights abuses in Papua, and teaming up with Solomon Islands, Vanuatu, New Caledonia's FLNKS, the United Liberation Movement of West Papua and the Pacific Islands Alliance of Non-Governmental Organisations, or PANGO.
Forum members include Australia, Cook Islands, Federated States of Micronesia, Fiji, Kiribati, Nauru, New Zealand, Niue, Palau, Papua New Guinea, Republic of Marshall Islands, Samoa, Solomon Islands, Tonga, Tuvalu and Vanuatu.