Status of tokamak physics

An overview of the status of tokamak physics is given in view of the needs for a tokamak reactor. In this paper a concise overview is given on the status of tokamak physics in the areas directly determining plasma fusion performance, i.e., on operational limits, plasma energy confinement and noninductive current drive. Operational limits arise owing to the presence of an upper bound to the plasma beta (defined as the ratio of the plasma kinetic pressure and the magnetic pressure of the confining magnetic field) and to the plasma density, and of a lower bound to the so-called safety factor. References are given to provide typical examples rather than to display priorities or the full data base