A recent methodological advance in legislative roll-call analysis is especially relevant to the study of legislative behavior outside the setting of the United States Congress. We argue that Poole's (2000) optimal classification method for roll-call analysis is preferable to parametric methods for studying many legislatures. This is because the nature of party discipline, near-perfect spatial voting, and parliamentary institutions that provides incentives for strategic behavior lead to severe violations of the error assumptions underlying parametric methods. The robustness of the nonparametric method to the stochastic nature of the data makes it an ideal candidate for studying strategic behavior in legislatures. We illustrate these points with an analysis of data from the French Fourth Republic (1946–1958).