William Ury is an American author, academic, anthropologist, and negotiation expert. He co-founded the Harvard Program on Negotiation and helped establish the International Negotiation Network with former President Jimmy Carter. Ury is renowned as the co-author of Getting to Yes with Roger Fisher, a seminal work that introduced the method of principled negotiation and popularized the concept of the best alternative to a negotiated agreement (BATNA) within negotiation theory.