This paper aims at highlighting how the etnographical approach can help us to open some "black boxes" of the quantitative approach of strike activity, which is the more current approach. At first, I will demonstrate how it can help us to understand how the perceptions of the trade-union representatives of their environment, their rivalry and the micro-context in which they act influence their strategy of striking. Secondly, I''d like to show how the internal diversity of trade-unions is one of the main factors that limit their capacity to strike, and explains the diversity in their manners to strike.
