People negotiate daily, often without considering it a negotiation. Negotiation occurs in organizations, including businesses, non-profits, and within and between governments as well as in sales and legal proceedings, and in personal situations such as marriage, divorce, parenting, etc. Professional negotiators are often specialized, such as union negotiators, leverage buyout negotiators, peace negotiator, or hostage negotiators. They may also work under other titles, such as diplomats, legislators, or brokers. There is also negotiation conducted by algorithms or machines known as autonomous negotiation. For automation, the negotiation participants and process have to be modeled correctly.