Origin and historical perspective on reactive metabolites -- Role of reactive metabolites in genotoxicity -- Bioactivation and inactivation of cytochrome P450 and other drug-metabolizing enzymes -- Role of reactive metabolites in drug-induced toxicity - the tale of acetaminophen, halothane, hydralazine, and tienilic acid -- Pathways of reactive metabolite formation with toxicophores/-structural alerts -- Intrinsically electrophilic compounds as a liability in drug discovery -- Role of reactive metabolites in pharmacological action -- Retrospective analysis of structure-toxicity relationships of drugs -- Bioactivation and natural products -- Experimental approaches to reactive metabolite detection -- Case studies on eliminating/reducing reactive metabolite formation in drug discovery -- Structural alert and reactive metabolite analysis for the top 200 drugs in the US market by prescription -- Mitigating toxicity risks with affinity labeling drug candidates -- Dealing with reactive metabolite-positive compounds in drug discovery -- Managing IADRs - a risk-benefit analysis