We began this chapter with a quick introduction to design patterns and discussed common patterns, such as restricting access, factory patterns, token systems, registries, and voting systems that are used for smart contract development. Then we moved on to understand the concept of decentralized autonomous corporations and society, and how they are different from DAOs. We explored a few crucial proposals related to Ethereum after understanding the proposal life cycle. Select case studies were picked to understand the future implications of consortium blockchains. We wrapped up the chapter by briefly introducing the world of graph-based distributed ledgers with GitHub analysis of the Iota cryptocurrency, and an introduction to Tangle.