Coronal mass ejections (CMES) are among the most dramatic forms of transient activity occurring in the solar atmosphere. Despite over twenty years of research, many basic questions related to the physics of CMEs have remained unanswered. Observations with the LASCO and EIT experiments on SOHO, combined with recent theoretical modeling, have provided new insights on some of these outstanding questions and have also raised many new ones that need to be addressed in the future. In this paper, we present some of the new results from SOHO pertaining to the source regions and onsets of CMEs, and their evolution in the corona. We emphasize the important role that studies of CMEs will play in the International Solar Cycle Studies program. (C) 2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.