As urban populations grow and cities face mounting sustainability and efficiency challenges, IoT technologies are emerging as critical enablers of smarter infrastructure systems. This thesis investigates how IoT-driven solutions transform municipal operations by embedding intelligent sensing and communication into everyday city functions. In smart traffic management, IoT enables dynamic traffic flow optimization, improves public transport scheduling, and enhances road safety through continuous monitoring. In waste management, it facilitates real-time bin level tracking, route optimization, and data-driven policy development to reduce operational costs and environmental strain. For energy efficiency, IoT supports automated lighting controls, energy usage analytics, and integration with decentralized renewable sources, thereby lowering carbon footprints and improving resilience. The work also addresses implementation challenges, including interoperability across heterogeneous systems, data privacy concerns, and infrastructure investment requirements. By evaluating both successes and limitations, the thesis provides a roadmap for urban planners, policymakers, and technology providers to leverage IoT for more sustainable, efficient, and livable cities.