Sui is a high performance Layer 1 blockchain designed using an object based resource model that provides strong asset safety and efficient processing. Its Move programming model, consensus structure, and validator design contribute to a secure and scalable foundation for Web3 applications. Despite strong protocol level security, DeFi applications built on Sui still depend on the quality of their own code and economic design. Real incidents and the Foundation’s security initiatives demonstrate the need for proactive and ecosystem wide security practices. As the Sui ecosystem matures, users and developers must apply due diligence and remain aware of project specific risks. With careful use, Sui can support safe and high growth applications across the decentralized finance landscape.