Cities are where humanity succeeds and fails. When cities actively recognise the need for economic, social and environmental sustainability and act accordingly, citizens have the opportunity to fulfil their potential. When social exclusion, environmental damage and lack of infrastructure are the norm, quality of life is irrevocably damaged. With some five billion people out of a total global population of eight billion forecast to be living in cities by 2030, urbanisation needs to be at the top of the agenda. The European Commission has been tackling this issue head-on. It recently published the 'World and European Sustainable Cities' report, which highlights European research activities designed to reconcile urbanisation with the need for sustainable and inclusive growth. A number of projects have focused on sustainability issues such as waste, water and energy and developed assessment tools for diverse regions such as coastal areas, mountains and other specific terrains. Within the field of transport, the possibility of buses running on hydrogen fuel cells or on biofuels has been investigated, with projects keen to show how the technology would work, whether it is safe and if it could be run autonomously. Best practice is crucial. In Brussels, for example, thirty years ago it was said that establishing cycle paths in the city would be impossible but through learning from other cities it was proved that such a scheme was feasible. The Commission believes that in such instances, benchmarking among cities is possible, and that other cities, whatever their situation, should be able to emulate and even compete in becoming the most "green city". Such changes improve quality of life, and when this happens, cities become not only happier and more attractive places, but also more productive. It is a fact that major European cities are incredibly diverse, and likely to become more so as people continue to flock to urban centres in search of work. According to UN-Habitat, the number of international migrants worldwide has more than doubled in 40 years, and in Europe the rise has been even steeper, doubling in just 15 years from 1985 to 2000. Cities offer job opportunities - of both high and low quality - and a high percentage of unqualified labour, the type of work local people try to avoid, is carried out by new arrivals. This trend is most visible in major European cities such as London and Paris, and the situation is compounded by the fact that a high percentage of immigrants very often speak a different language, follow a different religion and share different values to the majority of the population. Research here has focused not necessarily on integration, but on ways to fight poverty, the major barrier to integration. And the simple fact is that poor immigrants without access to decent education will find it very difficult to integrate. Demographic change in Europe (ageing population) makes it even more crucial to develop innovative integration policies. The second focus has been on providing access to information to enable further integration. A young immigrant in a European city, for example, might not be aware that free language classes are available just down the road. Integration into local lifehas also been studied. This 'ghetto effect' can be seen in numerous cities. Researchers have tried to gain an understanding of how to better recognise this challenge and support policy-makers. Inter-ethnic integration is vital if cities are to make full use of their human resources, and if all citizens are to enjoy equal access to opportunities. An increasing number of European cities are becoming aware that they need long-term, consistent integration policies in order to preserve both their viability as communities and their residents' quality of life. In Asian cities, which often tend to be compact, the only viable form of getting around is public transport, which is more environmentally efficient. In a sprawled city, such as Denver or Atlanta, mobility becomes five to six times more energy intensive. There is therefore a direct link between energy consumption and urban density. Living in a viable compact city means being able to shop, live and be entertained within a two or three kilometre radius. It is also a question of attitude; in Spain for example, it is normal for a residential building to contain a swimming pool, whereas in some other countries such a facility might be considered as something only for the rich. One issue researchers have to bear in mind is the historical legacy that cities bequeath. Buildings and roads - dating back sometimes to Roman times - have incredibly long time spans. This is why forward planning has finally been recognised as so vital; something built today can influence future planning for decades to come. Designing a forward-looking city today also involves looking at the economy of the future and asking pertinent questions: Will international trade continue to increase? Will the trend towards consuming locally produced goods take hold? Has globalisation peaked? How will the behaviour of people change in the next 30 to 40 years? The Commission recently completed a study entitled 'The World in 2025: Rising Asia and socio-ecological transition'. Among other things, the study noted a certain movement towards active ageing and towards territorial dynamics. While people want to leave work earlier in their lives, they are also living longer, a phenomenon that has led to growing recognition that in many countries the state will not be able to continue supporting retirees as it has. If the population continues to increase, how should basic needs such as water and energy be factored in? And what will be their costs? How are cities, rural areas and conurbations developing? These are difficult questions with no obvious answer. But EU research has confirmed one thing for certain: the challenges posed by urbanisation must be effectively addressed. The findings in the World and European Sustainable Cities report provide a detailed map of the road ahead. For more information, please visit: http://cordis.europa.eu/fp7/ssh/library_en.html Click here to see the report.