18 | Challenge 3: Smart Cities & Climate Change Challenge 3 on Smart Cities & Climate Change focused on the various elements of smart cities to help adapt to, slow down or mitigate the effects of climate change through ICTs. Challenge 3 ran from August until October and attracted 313 applications.Smart cities are one of the cornerstones of urban planning and technology today. Through a focus on reducing emissions, improving environmental sustainability, and innovations in green technologies, smart cities can lead the way in reducing human impact on climate change. Improvements in public services and the availability and use of ICTs make it possible for smart cities to reduce the negative effects on citizens’ health and wellbeing created by air pollution and global warming such as extreme weather events, the spread of epidemic and endemic diseases and food insecurity. Those already living in especially vulnerable areas, such as small islands states, developing communities or the areas around large cities, are especially well-placed to gain from the benefits Challenge 3 of smart cities. This challenge was organized in partnership with the World Health Organization (WHO).Socially conscious innovators and entrepreneurs have a crucial role to play in these changes. By working with transportation and public spaces, health infrastructure and public health efforts, education, civic engagement, ICTs and green technologies, entrepreneurs can help to create innovative solutions that better educate, empower and connect citizens.