A brief summary of recent research, primarily from the authors' laboratory, on polycyclic aromatic hydrocarbon carcinogens with respect to their DNA adduct formation, the mutational properties of these adducts and the effects of hydrocarbon dihydrodiol epoxide metabolites on the passage of cells through the cell cycle is presented. The concept of stealth properties of potent carcinogens, i.e. their ability to damage DNA without inducing a G1 arrest, is discussed. Also, mutation studies with dihydrodiol epoxide metabolites, the sequence-dependence of site-specific mutation, as well as the selectivity of hydrocarbon-DNA adduct formation are summarized.