A buy and sell agreement is a legally binding contract that specifies how share of a business partner may be reassigned if that partner dies or otherwise leaves the business. The buy and sell agreement is also known as a buy-sell agreement, a buyout agreement, a business will, or a business prenup.

This agreement makes it possible for the business to run smoothly in case of the either partner plans to exit out of the business, the other partner has the first right to buy the business and become a complete owner.