ZOPA, or Zone of Possible Agreement, refers to the range in a negotiation where two parties can find common ground. It represents the overlap between what each party is willing to accept, ensuring that both sides can reach a mutually beneficial agreement. Identifying the ZOPA is crucial for successful negotiations, as it helps parties understand their limits and the potential for compromise. By focusing on this zone, negotiators can work towards solutions that satisfy both sides, ultimately leading to a more effective and harmonious outcome.