Cities worldwide produce about two billion metric tons of municipal waste annually, with nearly half of this not being treated properly. This is a severe issue, particularly in less developed areas where waste management infrastructure is lacking. Often, up to 70% of this waste is organic and untreated, leading to significant methane emissions as it decomposes. A recent report from the United Nations Environment Programme (UNEP) forecasts that waste volumes could increase by two-thirds by 2050. The financial costs related to pollution, health issues, and climate impacts are expected to soar from $252 billion to $600 billion annually. The UNEP stresses the need for immediate action toward zero-waste strategies and better waste management systems. In the Global South, cities like Dar es Salaam and Rio de Janeiro, part of the C40 Cities network focused on climate solutions, are implementing effective waste management practices. They are pioneering the composting of market waste and converting organic refuse from schools and supermarkets into compost and biogas. These measures reduce methane emissions and provide societal benefits such as cleaner air and job creation in the green sector.