Since the coetaneous pioneering work of Crooks and Rudd at the University of Nebraska and of Harrison and Lucas at the University of Sussex on electron ejection at forward angles in ion-atom and ion-solid collisions, substantial and rapidly growing experimental and theoretical research concerning the physics of these processes has occurred. Because of the large volume of the new experimental and theoretical results, a two-day Symposium was held on related subjects hosted by the Physics Institute, University of Aarhus, Denmark, June 29-39, 1984. The present volume contains the Proceedings of this Symposium.