This book provides the most comprehensive treatment to date of the microphysical processes which lead to cloud and precipitation formation. Emphasis is placed on presenting a quantitative description of the various mechanisms (e.g. nucleation, diffusional growth and evaporation, collisional growth and breakup) which lead to the formation of cloud and precipitation particles, individually and in populations. The second edition of this highly acclaimed book has been extensively updated to incorporate new research reported in a large number of articles and dozens of books and conference proceedings published since the first edition. The book is directed primarily at undergraduate and graduate level students of cloud physics, as well as specialists in the field of aerosol physics, cloud dynamics, climate modelling, air chemistry, air pollution, and weather modification.