This handbook investigates ‘member-owned’ organizations, whether consumer co-operatives, agricultural and producer co-operatives, worker co-operatives, mutual building societies, friendly societies, credit unions, solidarity organizations, mutual insurance companies, or employee-owned companies. Such organizations can be owned by the consumers, producers, or employees—whether through single-stakeholder or multi-stakeholder ownership. ‘Employee-owned’ business means businesses where a significant proportion of the company is owned by its employees, whether as individual shareholders or through a trust, or some combination of the two; ‘significant’ is generally taken as at least 25 per cent. This complex set of organizations is named differently across countries: from ‘mutuals’ in the United Kingdom, to ‘solidarity co-operatives’ in Latin America. In some countries, such organizations are not officially recognized. For the sake of clarity, the handbook will refer to member-owned organizations to encompass the variety of non-investor-owned organizations, and in the national case-study chapters the terms used will be those most widely employed in that country. These alternative corporate forms have emerged in a variety of economic sectors in almost all advanced economies since the time of the Industrial Revolution and the development of capitalism, through the subsequent creation and dominance of the limited liability company. Until recently, these organizations were generally regarded as a rather marginal component of the economy. However, in recent years, they have come to be seen in some countries as potentially attractive in light of their ability to tackle various economic and social concerns, and their relative resilience during the financial and economic crises of 2007–2016.