Reference Data on Multicharged Ions summarizes spectroscopic and collisional atomic data for highly charged positive ions: oscillator strength, energy levels, transition .Probabilities, cross sections and rate coefficients of different elementary processes taking place in hot plasmas. The book does not give complicated theory and formulas; it presents the data in abbreviated form using tables, figures and, if possible, scaling laws for different characteristics. The data is interpreted on physical grounds, and ample references are given to the original literature.