Waste pickers play essential socioeconomic and environmental scenes in cities of developing countries. This study explored waste pickers to understand their socioeconomic characteristics, challenges, and roles in Tanzania cities. A mixed-methods research design was utilized, including questionnaires, interviews, and observations, to gather data from waste pickers in the city. The findings revealed that Arusha generates 550 tons of waste per day, with male waste pickers dominating the industry at 60%. Many waste pickers were within the active working age of 18-49 (90%), and two third possessed primary education (66%). Many waste pickers were single (50%) and married (42.5%). A significant portion of them (69%) were native to the region, while less than a third had migrated. On average, waste pickers in Arusha earn up to 153,000 TZS (USD 66) monthly, hence looking for an alternative job. Waste pickers also play a significant role in the city's informal economy. They act as recovery hubs and central suppliers of recycling materials. Their work helps extend the lifespan of landfills, conserve resources, and protect the environment. However, they face challenges such as low earnings, scarcity of materials, and health issues such as injuries, harassment, and low prices for materials. Formalizing and integrating waste pickers into the city's solid waste management system can reduce GHG emissions, providing a sustainable and meaningful model for managing waste and mitigating climate change in Arusha. The study underscores the importance of acknowledging and supporting the role of waste pickers in achieving sustainable waste management and a climate-smart city.