The private sector of a nation's economy consists of those entities which are not controlled by the state-i.e., a variety of entities such as private firms and companies, corporations, private banks, non-governmental organizations, and individuals.

A non-governmental organization (NGO) is a non-profit group or association that acts outside of institutionalized political structures and pursues matters of interest to its members by lobbying, persuasion, or direct action. The term is generally restricted to social, cultural, legal, and environmental advocacy groups having goals that are primarily noncommercial. NGOs usually gain at least a portion of their funding from private sources. Because the label "NGO" is considered too broad by some, as it might cover anything that is non-governmental, many NGOs now prefer the term private voluntary organization (PVO) or Private Development Organization (PDO).

The voluntary sector of a nation's economy consists of those entities which are not for profit and yet, at the same time, are not agencies of the state - e.g. charities, volunteer community centres and religious organizations. They may, in some countries, be subject to state scrutiny if they wish to qualify for charitable status.

Mission-based organization is often used as an alternative to terms such as non-profit and non-governmental organization. The latter define organizations in negative terms (i.e., "not for profit" or "not governmental"), rather than denoting an orientation to community service. Mission-based organizations range from formally incorporated foundations and philanthropic agencies to informal neighborhood groups that undertake an ad hoc project.

A state-owned enterprise (SOE) is an enterprise, often a corporation, owned by a state.

A nonprofit organization (abbreviated "NPO", or "non-profit" or "not-for-profit") is an organization whose primary objective is to support some issue or matter of private interest or public concern for non-commercial purposes. Nonprofits may be involved in an innumerable range of areas relating to the arts, charities, education, politics, religion, research, or some other endeavor.

The public sector IS that part of economic and administrative life that deals with the government- .i.e., economic policy ,education, government regulation, military.

An industry is generally any grouping of businesses that share a common method of generating profits, such as the "music industry", the "automobile industry", or the "cattle industry". It is also used specifically to refer to an area of economic production focused on manufacturing which involves large amounts of capital investment before any profit can be realized, also called "heavy industry." As-of 2004, Financial services is the largest industry (or category of industries) in the world in terms of earnings.