The anticipated growth in urban populations over the next few decades will inevitably pose huge challenges to infrastructure - from health services and schools to public transport and energy. So how can cities meet the needs of an expanding citizenry while at the same time being inclusive and sustainable?

The Habitat III conference, taking place in Ecuador's capital, Quito, from October 17-20, addressed this question and came up with the "New Urban Agenda" that aims to provide a road map for urban development over the next 20 years. DW spoke to Monika Zimmermann, deputy secretary-general of the ICLEI (Local Governments for Sustainability) World Secretariat. 

DW: Can you explain what the "New Urban Agenda" is?

Monika Zimmermann: The agenda is a document that has been heavily debated and discussed over the past few months.

It will guide the various actors, especially federal governments, on how to deal with urbanization and how to shift unorganized urbanization into what we call urban sustainable development, or sustainable urbanization.

So it can be thought of as a master plan for the next 20 years of urban planning?

That is what we hoped, but we're not so sure the document will fulfill that goal. We're a little disappointed - we'd hoped for a stronger new urban agenda, but at least it's a document in which many visions and goals are included, and which can lead many governments, research, businesses and civil society to take action, because in the end implementation is what will count.

How important are cities when it comes to putting the UN's Sustainable Development Goals and climate targets into practice?

Cities are not only crucial, they are the crucial factor. There's the famous statement from UN head Ban Ki-moon, who said the battle for sustainable development - and we could add for climate change too - will be lost or won in cities. We all know that the urbanization rate is growing dramatically. In a few years, two-thirds of all people in the world will live in urban areas.

We also know that the resource consumption of urban citizens is much higher than those of rural citizens. Another more positive aspect is that urban, and specifically dense, infrastructure also offers benefits.

For example, you can have much better public transport in a dense city. You can have different types of energy systems. So cities pose specific challenges, but they also offer specific opportunities.

Your network ICLEI encompasses about 1,500 towns, regions and megacities in more than 80 countries. Do these places share common challenges? Or are the challenges very different?

I think there are very common challenges - amazingly common challenges - but then of course there are also some which are more specific to the global north or the global south. A common challenge is the growing gap between what we know about what should be done, and the restrictions decision makers face to make it a reality.

In Germany, for example, we know that we have far too much traffic in our cities. It creates noise and air pollution, and we know what should be done - close the city centers off to cars, increase public transport, promote walking, cycling and other forms of sustainable mobility. But only a few cities have acted. Most don't dare, and that's partly because the decision makers fear citizens might not be so happy with restrictions.

Many cities have serious problems. If you have an urbanization rate where you get 10,000 new citizens each month - in some parts of Asia or Africa for example - it's not that easy to provide the necessary infrastructure, energy, water, transportation, schooling and so on.

Cities also struggle with increasing inequality. Large numbers of people live in slum areas, while at the same time there are skyscrapers and penthouses. How can urban planning address urban poverty and inequality?

The growing gap between the rich and the poor is one of the biggest challenges and concerns. We advise cities to do everything they can to close that gap and to equalize access to services, because that is one of the best investments in the future.

The transportation system, for instance, can determine how you can get to your workplace and how much you have to pay to reach your workplace. Renewable energy can also help with things like access to water and electricity. But there is no one recipe or solution.

What would you like the Habitat III conference in Quito to achieve?

We have 15 years left to fulfill the UN's Sustainable Development Goals, so the target year is 2030. I hope that by then we have broken the trend of increasing resource consumption, so the ideal sustainable city would be one where people don't consume more resources than what the Earth can replenish. A basic goal, but one that is still very difficult to reach. It would also be a city with a high quality of life, which comes from lower air pollution, better access to sanitation and health services, and where people feel they are respected as citizens.

Do you have a good example where it's already happening?

It is happening in many places, but I don't think the sustainable city exists yet. Many cities are very good in one or two specific areas, but they might be lacking in another area. A famous example is Copenhagen, which has completely changed the transportation behavior of its citizens. Many travel by bicycle or walk.

There are also cities like Vancouver or Malmo, which have set themselves future targets of using 100 percent renewable energy. Although they often face much more difficult conditions, cities in the global south are also ambitious. Kasese in western Uganda, a city of 700,000 inhabitants, is aiming to supply a lot of its energy through renewables in the future. From a natural conditions perspective, they might be in a much better situation than somewhere like Copenhagen, but from a governance and technology perspective, of course they struggle much more. These are the organizational and financial aspects that cities often need help with.

Monika Zimmermann is the deputy secretary-general of the ICLEI World Secretariat. She joined ICLEI in 1993 when she started to build up the International Training Center at ICLEI European Secretariat. She joined the World Secretariat in 2010, where she manages the teams working on global events, knowledge management, urban research, ecomobility and future city leaders.