Electing the European Parliament: How uniform are 'uniform' electoral systems?

In 2002 agreement was reached on new uniform, electoral procedures for European Parliament elections. This article does two things. First, it provides a comprehensive account of the rules under which the EP was elected in 2004, revealing a high degree of continuing variability in the existing electoral systems across all 25 Member States. Second, it addresses the question: if the electoral systems vary in form, do they also differ significantly in their effects?