Large increases in the world population, coupled with people movement from place to place have been causing rapid increases in urbanization. In 2015, more than half of the world’s population- close to 4 billion people- lived in cities. In 2030, it is projected that the number will be around 5 billion; in other words, every 6 out of 10 people will be living in cities.
This rapid urbanization is changing the landscape of human settlement. People usually move to cities to benefit from their economies of scale, such as, the provision of goods, services and transportation.  However, increased urbanization brings about enormous challenges to policymakers and populations worldwide. These include, for example, increasing numbers of slum dwellers, increased air pollution, inadequate basic services and infrastructure, and unplanned urban sprawl, which also make cities more vulnerable to disasters.
According to UN Statistics, almost a third of the urban population in developing regions still live in slums. In fact, despite that the proportion of the urban population living in developing country slums fell from 39 per cent in 2000 to 30 per cent in 2014, the absolute number of urban residents who live in slums continued to grow. Thus, in 2014, the UN estimated that around 880 million urban residents lived in slum conditions, compared to 792 million urban residents in 2000.
Another challenge of rapid urbanization is the management of solid waste, and ensuring the city has the right infrastructure and facilities to dispose of and/or recycle waste efficiently. Uncollected solid waste blocks drains causes water and air contamination and may lead to the spread of diseases. For a few years now, Lebanon has been a sad example of the dangerous impact of the absence of a sound waste-management policy. On the basis of data from cities in 101 countries from 2009 to 2013, 35 per cent of the urban population was still not served by municipal waste collection services. 
Another challenge is air pollution, which causes a major environmental health risk. According to the WHO, in 2014, 9 of 10 people who lived in cities were breathing air that did not comply with the safety standard set by WHO. 
All this culminates to show the grave importance to the 11th goal of the 2030 Sustainable Development Agenda, which is to “Make cities and human settlements inclusive, safe, resilient and sustainable.”
World leaders have called, in this Goal and its accompanying targets, for concerted action to address this challenge and enhance cities’ resilience because they will eventually remain the destination of people seeking greater opportunities in life. Hence the need for informed, participatory and strategic planning to protect cities and harness their potential in becoming growth-centres for economic and social development.
The UN estimates that as of May 2017, 149 countries were developing national-level urban policies.  In fact, during the recent High Level Political Forum held in New York in July 2018, progress in Goal 11, among others, was assessed. Of the Arab countries presenting their Voluntary National Reviews, Meera AlShaikh, Project Manager at Smart Dubai, United Arab Emirates (UAE), presented Dubai’s strategies for providing solar energy, increased use of recycled water, and various technologies including blockchain, AI and ICT services to enable Dubai’s transformation as a smart city.  Lebanon’s VNR presentation emphasized the country adopted a bottom-up approach to SDG implementation, highlighting progress in heath, poverty reduction and development of small and medium enterprises, all important but not enough steps towards realizing sustainable cities.
And since SDG 11 is directly impacted by urbanization and population movements, it is imperative for Arab countries to study avenues of cooperation in achieving the SDGs, particularly SDG 11. Rohit Aggarwala, Columbia University, noted there is no “one size fits all” formula for achieving the various SDG 11 targets, and called for thoughtful and comprehensive management of urban issues and appropriate distribution of powers. Other speakers emphasized the need for finding new approaches to citizen participation, cities’ connections with rural ecosystems, post-disaster management, addressing particular needs of women, persons with disabilities, youth, and elderly persons, migrants and refugees. Participants in the HLPF also highlighted the need for “smart city” approaches that not only promote the use of digital technologies but also increase social inclusion, environmental sustainability and quality of life for urban residents.
The writer, Rasha Salman, is National Information Officer at the UN Information Centre in Beirut and has an MPhil in Development Studies from the University of Cambridge. She contributed this article to The Jordan Times.