A buy-sell agreement is a legally binding contract between business partners that restricts the sale of one partner’s interest to an outside party. The agreement sets out the conditions under which a partner’s interest may be sold, and how it will be valued. It also typically includes provisions for the purchase of a partner’s interest in the event of death, disability, or retirement. A buy-sell agreement is an important tool for businesses to protect the business in the event of a partner’s departure.