A shareholders’ agreement is contract between the owners (shareholders) of a firm, defining their mutual obligations, privileges, protections, and rights.
A partnership agreement is written agreement between two or more individuals who join as partners to form and carry on a for-profit business. It regulates the (a) nature of the business, (b) capital contributed by each partner, and (c) their rights and responsibilities. A partnership does not have a separate legal existence as is seen with an incorporated business, and the partners are jointly and severally liable for the debts of the firm. Even on withdrawing from the partnership, a partner may remain liable for the partnership’s debts.