In this essay I would like to outline and analyse various options for structuring a class action lawsuit . First, I will examine the form of class action lawsuit that is best known internationally, the United States of American class action, with a view to showing the extent to which its negative impacts are linked to particular institutions of US law. I will proceed to examine European forms of collective legal protection that are thought to be appropriate to today's needs. The subsequent economic analysis sets out to evaluate the different possible structures for class action lawsuits with reference to the goal of economic efficiency .