At the center of a co-op is the concept of equality. Although it is an economic model, it can be applied to a large number of other circumstances, such as consumer cooperatives, housing cooperatives, credit unions, workers` cooperatives and various public utility formats. A trade union is a self-organizing group of individuals, companies or entities formed to carry out certain operations or promote a common interest. It can also facilitate criminal activities and organized crime. The term is sometimes associated with anarchist theory, especially anarcho-unionism, which constitutes an alternative to both the nation-state and capitalist enterprises. . . .