These proceedings bring together ideas from solar and stellar physics. The sun is near enough for rather detailed observations and one chapter is devoted to the more recent experimental data from observations from space. On the other hand the multitude of stars provides a wide range of physical parameters to test hypotheses in solar and stellar astrophysics. The reader will find an illuminating overview of these fields ranging from the dynamo in the convection zone to the stellar envelopes and winds in the outer regions. In particular the importance of small-scale magnetohydrodynamic processes for the activity phenomena plays an important role in the contributions to this volume. For both students and researchers the general introduction by N. O. Weiss makes an excellent guide to this very active field of research. (See also Lecture Notes in Physics Vol. 291.)