a1 UMR 6525 H. Fizeau, Université de Nice Sophia Antipolis, Centre National de la Recherche Scientifique, Observatoire de la Côte d'Azur, Boulevard de l'Observatoire, B.P. 4229 F 06304 Nice Cedex 4 - France. email: email@example.com
In this review I will present recent results between 2007 and 2011 based on interferometric observations of binaries and multiple systems with the VLTI, NPOI, SUSI and CHARA instruments. I will also explain the kind of constraints an interferometer can provide in order to better understand the physics of multiple systems.