In the monograph issues of artificial regulation of atmospheric precipitation and fog dispersion, including physical principles of weather modification, technical means and reagents to effect on clouds and fog are considered. The description of numerical models used in works on weather modification activity is presented and results of theoretical researches of the effectiveness of impact on clouds and fog are presented. The technology of planning is described and results of experimental studies and pilot works on artificial regulation of precipitation and weather protection of large cities are presented. Ecological aspects of weather modification are considered.