A Bougainville leader, Joseph Kabui, says he believes the third and final draft of the island's constitution will be acceptable to the Papua New Guinea parliament.
The Bougainville Constitution Commission has finished several months addressing concerns raised by the second draft.
Early next month the Bougainville Constituent Assembly will meet to consider the changes.
Mr Kabui says these include cutting the number of seats in the planned House of Representatives from 51 to 41.
He says this follows national Government concerns about the costs of the House, but he is not envisaging Port Moresby will have any further worries.
"...All the problems, the issues that the national Government, even the Attorney General's office had, and then of course the Bi-Partisan Committee had, have been addressed by the Commission as we went along, making amendments here and there as we went along."