Blockchain technology is increasingly being used in various industries, including finance, healthcare, energy management, digital records, and IoT. The combination of IoT and blockchain can address privacy, security, and responsibility issues in data-driven environments. Ethical issues are discussed in this chapter, emphasizing responsible governance frameworks. Blockchain-based decentralized systems can empower residents by giving them more control over their data and increasing transparency in municipal government. Ecologically sound architecture strategies prioritize user comfort, security, modernization, and data security. Blockchain technology can address technical and administrative tasks, such as data security and sustainability issues. The advancement of blockchain technology with IoT makes smart cities more secure and user-friendly in various sectors.