Partnerships are also frequent regardless of and among sectors. Non-profit organizations, for example, may partner together to increase the likelihood of each achieving their mission. Governments may partner with other governments to achieve their mutual goals, as may religious and political organizations. In education, accrediting agencies increasingly evaluate schools by the level and quality of their partnerships with other schools and across sectors. Partnerships also occur at personal levels, such as when two or more individuals agree to domicile together. Partnerships between governments, interest-based organizations, schools, businesses, and individuals, or some combination thereof, have always been and remain commonplace.

Partnerships have widely varying results and can present partners with special challenges. Levels of give-and-take, areas of responsibility, lines of authority, and overarching goals of the partnership must all be negotiated. While partnerships stand to amplify mutual interests and success, some are considered ethically problematic, or at least debatable. When a politician, for example, partners with a corporation to advance the corporation's interest in exchange for some benefit, a conflict of interest may make the partnership problematic from the standpoint of the public good. Developed countries often strongly regulate certain partnerships via anti-trust laws, so as to to inhibit monopolistic practices and foster free market competition.

Among developed countries, business partnerships are often favored over corporations in taxation policy, since dividend taxes only occur on profits before they are distributed to the partners. However, depending on the partnership structure and the jurisdiction in which it operates, owners of a partnership may be exposed to greater personal liability than they would as shareholders of a corporation.

In civil law systems, a partnership is a nominate contract between individuals who, in a spirit of cooperation, agree to carry on an enterprise; contribute to it by combining property, knowledge or activities; and share its profit. Partners may have a partnership agreement, or declaration of partnership and in some jurisdictions such agreements may be registered and available for public inspection. In many countries, a partnership is also considered to be a legal entity, although different legal systems reach different conclusions on this point.

Partnerships may be formed in the legal forms of General Partnership (Offene Handelsgesellschaft, OHG) or Limited Partnership (Kommanditgesellschaft, KG). A partnership can be formed by only one person. In the OHG, all partners are fully liable for the partnership's debts, whereas in the KG there are general partners with unlimited liability and limited partners whose liability is restricted to their fixed contributions to the partnership. Although a partnership itself is not a legal entity, it may acquire rights and incur liabilities, acquire title to real estate and sue or be sued

In mainland China, a partnership enterprise encompasses two types of partnerships：general partnerships and limited partnerships. A general partnership comprises general partners who bear joint and several liabilities for the debts of the partnership enterprise. There is a special general partnership which can be employed by professional service providers such as accountant firms and law firms. A limited partnership enterprise includes general partners and limited partners where the limited partners are liable only to the extent of their capital contributions.

The Japanese civil code provides for partnerships by contract, which are commonly known as nin'i kumiai (任意組合?) or "voluntary partnerships." A more recent statute has allowed for the creation of limited liability partnerships.

One form of partnership unique to Japan is the tokumei kumiai or "anonymous partnership," in which partners have limited liability so long as they remain anonymous in their capacity as partners and do not participate in the operation of the partnership. Japan provides for partnership-like corporations called mochibun kaisha.

Under common law legal systems, the basic form of partnership is a general partnership, in which all partners manage the business and are personally liable for its debts. Two other forms which have developed in most countries are the limited partnership (LP), in which certain limited partners relinquish their ability to manage the business in exchange for limited liability for the partnership's debts, and the limited liability partnership (LLP), in which all partners have some degree of limited liability.

There are two types of partners. General partners have an obligation of strict liability to third parties injured by the Partnership. General partners may have joint liability or joint and several liability depending upon circumstances. The liability of limited partners is limited to their investment in the partnership.