that are responsible for the visible aurora, the recognition of the fundamental role of the large- scale current systems in organizing the auroral mor­ phology, and of the interplay between particles and electromagnetic fields. The project began in March 1999, as a natural follow-up of the project on Magnetospheric Plasma Sources and Losses that resulted in volume 6 of this se­ ries, with a planning meeting by a core-group that coordinated the project. The group consisted of J. E. Borovsky, Los Alamos National Laboratory; C. W. Carl­ son, University of California, Berkeley; G. Haerendel, Max-Planck-Institut fur ex­ traterrestrische Physik, Garching; B. Hultqvist, Swedish Intitute ofSpace Physics, H. E. J. Koskinen, Finnish Meteorological Institute, Helsinki; W. Lotko, Kiruna; Dartmouth College, Hanover, New Hampshire; K. A. Lynch, University of New Hampshire, Durham and G. Marklund, Royal Institute ofTechnology, Stockholm. G. Paschmann, ISSI, Bern, was the project leader.