The article is an attempt to look at smoke agents as a significant tool which, when used appropriately, may decide on the combat operation success. General rules and aim of using smoke agents on the battlefield have been presented in the introduction. A special attention has been drawn to factors that influence these agents effectiveness. Then the article characterises the rules of using smoke agents in selective kinds of military operations, i.e. defensive, offensive and other kinds of operations. The ways to use all kinds of smoke screens (obscuration, blindness, indication, apparent and protective ones including) have been discussed.