The contents of this volume are based largely on a symposium on cloud dynamics held in Hamburg, Germany, as a part of the Third General Assembly of the International Association of Mete- orology and Atmospheric Physics (IAMAP), 17-28 August-1981. Plans for this symposium were initiated by the Cloud Dynamics Group, appointed through the International Commission for Dynam- ic Meteorology (ICDM), IAMAP. Members of this group are Bruce Morton - Chairman, Australia; Tomio Asai - Secretary, Japan; E. M. Agee, USA; V. Andreyev, Bulgaria; K. Fradrich, FRG; M. W. Moncrieff, UK; R. S. Pastushkov, USSR; J. P. Chao, PR China; Bh. V. Ramanamurti, India; W. Roach, UK; J. Simpson, USA; J. T. Steiner, New Zealand; M. Yanai, USA. E. M. Agee served as con- vener of the symposium in Hamburg. Dynamic meteorology has grown rapidly and covered a great variety of fields since the foundation of ICDM, making it increas- ingly difficult for the Commission to manage all activities. In order to improve this situation, some ad-hoc Working Groups within ICDM were organized at the 1977 IAMAP meeting in Seattle. Each of these working groups, such as the one in Cloud Dynamics, deals with a particular sub-field of dynamic meteorology.