Cross-border co-operation on planning issues could bring economic and social prosperity, it has been claimed.
Northern Ireland Environment Minister Alex Attwood said there should be greater collaboration between Belfast and Dublin to develop an all-island approach to health, roads, water and waste.
"An all-island spatial strategy may be a 'no-go zone' for some - however, I believe it is the best future for us all. In the absence of this we have duplication, less cohesion, less impact, more cost," he said.
Mr Attwood was addressing around 200 delegates at the Irish Planning Institute's annual conference at Belfast City Hall.
Planning reform in Northern Ireland; local government reform in the Republic; opportunities in cross-border and coastal planning; renewable energy and lessons in city regeneration are among the topics up for discussion during the two-day conference
"We have to learn from best practice and avoid the worst practice of planning devolved to local councils in Scotland and Ireland. Local plans done well can liberate local areas. We can see that in other places. We can replicate this here if we get the transfer of planning done right. This is the prize. We can secure it," added Mr Attwood.
Joanna Kelly, president of the Irish Planning Institute, claimed increasing pressures for cross-border developments like fracking projects and wind farms meant north/south co-operation was crucial.
"All national and regional policy documents throughout the island of Ireland should be strategically aligned so that the public policies are consistent," Ms Kelly said.
She also called for a reduction in the amount of red tape and said more must be done to educate the public about the planning system. She added: "The public must understand how their local government and planning system works. We need to ensure that everyone understands the principles of good planning and why certain decisions are made."
Meanwhile, Jan O'Sullivan, the Republic's Minister for Housing and Planning, said both sides of the border had much to learn from each other. She said: "Increasing collaboration across administrative and political boundaries will ensure the planning process gives certainty to both communities and investors, whether in the north or in the south and in relation to defining future development priorities and possibilities."