Solidarity unionism is a model of labour organizing in which the workers themselves formulate strategy and take action against the company directly without mediation from government or paid union representatives. It is a key pillar of anarcho-syndicalism

Anarcho-syndicalism

Anarcho-syndicalism is a branch of anarchism which focuses on the labour movement. The word syndicalism comes from the French word syndicat which means trade union , from the Latin word syndicus which in turn comes from the Greek word σύνδικος which means caretaker of an issue...

. Organizations which use the model of solidarity unionism, such as the Industrial Workers of the World

Industrial Workers of the World

The Industrial Workers of the World is an international union. At its peak in 1923, the organization claimed some 100,000 members in good standing, and could marshal the support of perhaps 300,000 workers. Its membership declined dramatically after a 1924 split brought on by internal conflict...

, state that putting power directly into the hands of the workers prevents an otherwise inevitable crust of bureaucrats from forming within the organization. This is why organizations which use the solidarity unionism model often refer to other sorts of labour organizing as bureaucratic unionism

Craft unionism

Craft unionism refers to organizing a union in a manner that seeks to unify workers in a particular industry along the lines of the particular craft or trade that they work in by class or skill level...

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