Sky Dollar (USDS) is a decentralized stablecoin introduced with the Sky Protocol rebrand in 2024, serving as an upgraded alternative to DAI. Designed to maintain a soft peg to the U.S. dollar, USDS is backed by surplus collateral and stabilized via Peg Stability Modules (PSMs), which allow for direct, predictable exchanges with other stablecoins such as USDC and USDT. As a core asset within its ecosystem, USDS enables users to access a range of decentralized financial services: it can be deposited in savings modules to earn interest, used to obtain governance rewards in the form of SKY tokens, and traded across various liquidity pools. In addition, holding USDS empowers users to participate in on-chain governance decisions. By combining stability, broad utility, and self-custody, USDS represents a significant evolution in decentralized finance.