The dabbawalas of Mumbai are a large supply chain service that delivers home-cooked meals to office workers. They operate a complex distribution network involving sorting, coding, and relaying of tiffin carriers ("dabbas") through Mumbai's suburban railway system. Key aspects of their operations include a decentralized three-tier structure, a coding system that relies on minimal literacy, and a culture of reliability, equality, and customer referrals rather than a traditional business model. While facing challenges from changing lifestyles and workforce demographics, the dabbawalas have continued to successfully deliver over 350,000 meals per day with an extremely low error rate through their robust yet low-tech distribution system.