Cities are responsible for approximately 70% of the world s greenhouse gas (GHG) emissions and are recognized as key players in the transition to a low-carbon economy. The global net zero approach creates growth opportunities for cities to partner with a diverse set of businesses across the value chain to move from decarbonization planning to action. The race toward climate-neutral and smart cities is on, with 100 European cities planning to become net zero by 2030. The European Union goal of achieving climate neutrality by 2050 begins with these cities and will be followed by the entire region and, eventually, the entire world. A collaborative approach to climate action enables the integration of finance, climate, and technology across sustainable city planning. Urgent, collaborative, multilateral, smart, technology-driven, and digital actions are necessary and achievable. Cities are taking a holistic approach to reduce emissions. Digital solutions help them to develop, manage, and execute climate action plans by transforming activity-based data into actionable insights and applying AI for extrapolation and forecasting to change responsibilities and challenges into business opportunities to generate revenue. The top growth opportunities in air quality and emissions management consider strategic imperatives and growth opportunities, with an overview of companies to action and growth accelerators. Opportunities include real-time carbon tracking for climate-smart cities; marine fleet carbon tracking; carbon removal technologies for businesses; indoor air quality monitoring; and Earth observation satellite imagery and AI-based digital twins to identify emission hot spots. Author: Paulina Blaszczyk