Zone of possible agreement

The term zone of possible agreement (ZOPA), also known as zone of potential agreement [1] or bargaining range,[2] describes the range of options available to two parties involved in sales and negotiation, where the respective minimum targets of the parties overlap.

Where the parties have a small ZOPA, the difficulty lies in finding agreeable terms.

To determine whether there is a positive bargaining zone each party must understand their bottom line or worst case price.

A ZOPA exists if there is an overlap between each party's reservation price (bottom line).

[4] It occurs when people negotiate and cannot reach a ZOPA,so they are in negative bargaining zone.

A negotiator should always start considering both parties' ZOPA at the earliest stage of his or her preparations and constantly refine and adjust these figures as the process proceeds.