Joël Perret-Liaudet graduated in Engineering and holds a PhD from École Centrale de Lyon. He is Associate Professor within the Tribology and System Dynamics Laboratory (UMR CNRS 5513), at École Centrale de Lyon where he holds this position since 1992. He teaches courses generally in the fields of Mechanical Engineering and Solid Mechanics. In 1999, Joël Perret-Liaudet obtained an accreditation to supervise research in the field of dynamics and vibrations of parametric and/or nonlinear mechanical systems. He is interested mainly in research concerning the vibroacoustic mechanisms, including the gear transmission, in its global and local approaches. Furthermore, his work focuses on understanding various dynamic, vibration and acoustic phenomena coupling with contact mechanics and friction.