The importance of mechanical energy in driving life in aquatic systems has been known for several decades. However, the role of small-scale physics in plankton ecology is still controversial. Due to the difficulty in describing turbulent flows at such small scales, significant progress requires close collaboration between biologists and physicists. This volume collects a set of lectures presented during in the Advanced Study Course "Ocean Turbulence: a basic environmental property for plankton" held in Barcelona in September 1995. This course was part of the training actions developed within the Marine Science and Technology (MAST) program of the European Commission. The organization of the course and the edition of this book have aimed to stimulate multidisciplinary approaches within the scientific community to address this topic.