The World Parks Congress has been organized by IUCN every decade since 1962. The first two Congresses were held in the USA (Seattle, 1962; Yellowstone and Grand Teton National Parks, 1972), with the next three in developing countries (Bali, Indonesia, 1982; Caracas, Venezuela, 1992; Durban, South Africa, 2003). (Full disclosure: I was Deputy Secretary-General at Bali and Secretary-General at Caracas). Sydney, Australia, hosted the sixth Congress on 12–19 November 2014, welcoming over 6,000 participants from 170 countries. The purpose of the Congresses, broadly speaking, is to review progress in protected areas over the previous decade, assess the current state of protected areas, and chart a course for the coming decade.

Protected areas continue to grow in importance as a land-use. The latest assessment lists over 200,000 protected areas, covering 15.4% of the land and inland waters and 8.4% of seas within national jurisdiction. This brings within reach the Convention on Biological Diversity's target of 17% for terrestrial protected areas and 10% for marine protected areas by 2020. Percentage coverage is easiest to track but improving ecological representation, management effectiveness and connectivity are perhaps more important to the success of protected areas, although more difficult to measure.

So while much of the Congress celebrated success, storm clouds loomed over the gathered masses. The expansion of the number and size of protected areas carries a price tag that many governments are finding difficult to pay, in terms of both social and economic costs. When protected areas covered less than 4% of the land, it was possible to think of them as ‘untouched’ and protected from human disturbance. But new approaches are needed when responsibilities have grown so substantially, along with the pressures of a growing and wealthier population that often seems reluctant to face serious environmental issues.

The effective design, management and governance of protected areas have therefore become significant political issues. Many symptoms were on display in Sydney. Some governments are reducing their financial support to protected areas or even eliminating some. World Heritage sites, established because they are ‘of outstanding universal value’, are not immune. For example, Indonesia's growing demands for economic expansion are leading to significant encroachment on the Tropical Rainforest Heritage of Sumatra, a World Heritage Property that includes iconic sites such as Sumatra's Gunung Leuser National Park, home of Sumatran rhinos, orangutans, Asian elephants and many other species categorized as threatened on the IUCN Red List. The spread of oil palm, driven by global markets, is making a mockery of this natural heritage and more widely posing a scourge on Southeast Asia's tropical forests and the protected areas established to conserve them for public benefit.

Even the host country, Australia, is no longer an enlightened model for protected areas. Under economic and political pressure, the Great Barrier Reef Marine Park, a World Heritage site, is suffering from overfishing and the construction of three new harbours for exporting coal, a major contributor to climate change. Perhaps even worse are plans to open up 75,000 ha of the Tasmanian Wilderness World Heritage Area to logging.

Each World Parks Congress seeks to be innovative, but the issues are familiar. The first Congress, in 1962, already called on governments to include protected areas in their development plans, establish more marine protected areas, and give more attention to tropical forests. So what was new in Sydney?

The link between protected areas and development was given a new twist by emphasizing that protected areas provide a strong return on investment in terms of the ecosystem services they provide. In other words, protected areas are not set aside; rather, they are allocated to conserve nature and ecosystem services to support society.

Marine protected areas were highlighted in Sydney. Their success in protecting species and ecosystems will depend on political arrangements with other constituencies that have marine interests, including fisheries agencies, fishing communities and the private sector. Reaching marine protected area targets will require much stronger international political support through the Law of the Sea for areas beyond national jurisdiction.

Much of the recent expansion of terrestrial protected areas, not surprisingly, has taken place in the more remote areas of countries long occupied by politically marginal indigenous peoples, subsistence farmers and herders. Now, the affected peoples are becoming politically mobilized, insisting on greater consultation, appropriate compensation and even a voice in management. They argue that those who live closest to nature have the greatest interest in protecting it, although results are widely variable in practice. Led by Australian aborigine groups at the Congress, a broad political agreement was reached that protected areas can meet their objectives only if they have good relations with the local people. This will require giving them a stronger voice in protected area management. But this does not mean opening up protected areas to local communities, any more than a banker opens his vaults to the public he serves; rather, protected area managers, like bankers, should manage their assets to provide sustainable benefits to their ‘customers’.

The Congress also added its voice to the growing chorus of alarm about wildlife crime becoming part of globalized criminal organizations. Many governments are now treating poaching, habitat encroachment and illegal logging as threats to national security, moving the issue higher on the political agenda. While the causes of such crime need international political attention from Interpol, UN agencies, trade organizations and government law enforcement agencies, protected areas must deal with the symptoms. Protected area agencies were urged to improve the equipment, training and working conditions of the rangers who are risking their lives to protect valuable natural resources. But even this will be insufficient without broader political support at local and national levels.

Economic language was heard a lot in Sydney, perhaps to communicate protected areas issues more effectively to the politicians who set policies and budgets. Terms such as ‘natural capital’ and the ‘economics of biodiversity loss’ helped to express protected area values. Protected areas were shown to provide ‘public goods’ in the form of ecosystem services, earning a significant return on investments and therefore worthy of greater support as part of public budgets. A focus on the values of protected areas to society could expand their constituency. Victoria Parks, for example, effectively promoted its Healthy Parks, Healthy People initiative, earning public support through encouraging more people to enjoy the outdoors and the multiple health benefits that can follow. Protected areas were also recognized for their contributions to reducing risks to food security and helping address the effects of extreme natural events.

With half the world's people living in cities, protected area agencies must reach out to the urban constituency. Some major cities, such as Rio de Janeiro, Sydney, Nairobi, Hong Kong, Cape Town, San Francisco and London, have significant protected areas within them or on their boundaries. A third of the 100 largest cities depend on protected areas for their water supply, and protected areas depend on cities for political and social support, including through urban people visiting the protected areas and voting for politicians who support them.

Climate issues, already raised at the 1992 and 2003 Congresses, received greater attention at Sydney, reflecting their place on the political agenda. The links between climate change and ecosystem services were highlighted, along with the role of protected areas in helping the public understand climate change and its implications for people. Protected areas may store more carbon than any other land or sea use, especially in old-growth forests, wetlands, mangroves and coral reefs. Protected areas can help adapt to climate change by linking sites to enable species' movements, becoming part of regional land-use strategies, and conserving ecosystems that reduce the risks of damage from extreme natural hazards. Protected areas need to become a politically palatable investment in addressing climate change.

Insufficient political support reflected by budgetary constraints is also pushing protected area agencies to work more closely with the private sector. Companies have expertise in management, technology, finance, spatial planning, political influence and other fields that could be useful to protected areas. Many protected area agencies remain cautious about working with the for-profit sector, insisting on no-go status for at least some categories of protected areas. In the coming years protected area agencies will need to become more businesslike, finding politically acceptable ways to work more efficiently and develop creative ways to finance protected area operations. The entrepreneurial skills of the private sector could be helpful in this regard, although private profit motives must not trump the public good of conserving nature.

The Sydney event brought the political dimension of protected areas into sharper focus, although sadly it did not take full advantage of the opportunities available by giving political issues a more explicit focus and a media splash at the event's conclusion. After all, protected areas are a reflection of public will, so the public constituency for protected areas needs to be strengthened and mobilized to ensure they can stand up against those who would prefer to use protected area resources for private gain. For the first time at a World Parks Congress, youth was identified as its own constituency and given a significant portion of the agenda, a shrewd political move for an important demographic that is ready to step up.

The major Congress outcome, called The Promise of Sydney, will be released online only in March 2015, with a Vision statement, 12 Innovative Approaches to transformative change, a Panorama of Inspiring Protected Area Solutions, and Promises by governments, funders and NGOs to improve protected area management.

A continuous flow of results from the Congress is available at www.panorama.solutions. Out of the chaos of 6,000 people, each with enlightening stories to tell and too little time to tell them, will come the Promise of Sydney. The future of human well-being may well depend on keeping the promises made. The political dimension will be critical to their success.