This article presents a new set of experiments using the "sentence-matching paradigm" (Forster, 1979; Freedman and Forster, 1985; see also Bley-Vroman and Masterson, 1989), investigating native speakers' and second language (L2) learners' knowledge of constraints on clitic placement in French. Our purpose is three-fold: (1) to shed more light on the contrasts between native speakers and L2 learners observed in previous experiments, especially Duffield and White (1999), and Duffield et al. (2002); (2) to address some of the specific criticisms of the sentence-matching paradigm levelled by Gass (2001); and (3) to provide a firm empirical basis for follow-up experiments with L2 learners. The results reported here provide some confirmation of the validity of Duffield et al.'s earlier work, and help to adjudicate among competing interpretations of the previous effects. (Contains 4 figures, 2 tables and 14 footnotes.)