The Global Environment Outlook assessments are a rich and valuable resource for decision-makers, practitioners and researchers about the current state of the environment with in-depth scientific knowledge. The Global Environment Outlook for Cities is an opportunity to distil this information for the critical urban stakeholder audience. Increasingly cities are recognized as central to the global environmental situation, from climate change to air pollution and while urban residents suffer many consequences of environmental degradation, cities are also sources of innovation and inspiration for tackling these difficult challenges. Through the Global Environment Outlook for Cities, we hope to empower and embolden city leaders, urban experts and everyone interested in cultivating healthy and liveable cities now and for future generations. Building on the scenarios, pathways and findings of the sixth edition of the Global Environment Outlook, the Global Environment Outlook for Cities will cover in depth the environmental issues relevant for cities as well as the urban characteristics that shape environmental solutions within and beyond urban boundaries. Furthermore, the Global Environment Outlook for Cities will examine the potential for transformative pathways tackling socio-economic and environmental issues in the face of climate change and continued urbanization.