Zone of possible agreement

A zone of possible agreement (ZOPA), also known as a bargaining range, is a term used to describe a ‘zone’ within negotiations where there is the potential for two parties to agree. No amount of negotiation relating to terms outside the ‘zone’ will lead to an agreement.

Successful negotiation depends upon establishing a ZOPA that is understood by both parties. This requires the two parties to discuss and explain their own interests and values, as well as their ‘bottom line’ – the boundaries of their zone, outside of which they cannot agree. Ideally, this should be done early in the negotiation process.

An example is if a contractor wishes to negotiate a fee for works with a client. They will not accept less than X amount, and the client is unable or unwilling to pay above Y amount. If those two amounts overlap then that is the ZOPA.

[edit] Related articles on Designing Buildings Wiki

• Alternative dispute resolution.
• Bid strategies.
• Contract negotiation.
• Expert determination.
• Game theory.
• Negotiation techniques.
• Tender negotiations.