This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book focuses on an important aspect of laboratory animal inhalation studies. It describes the prevention of disease, provisions for comfortable housing, and maximizing the study benefits while minimizing the stresses. The book also focuses on nose-only exposures — perhaps the most versatile method of inhalation exposure. It covers methods used to monitor animals during their exposure. Such monitoring is useful both to observe effects and to estimate the inhaled “dose” of the study material. The book explains the anatomical methods used for acquiring and preparing tissue samples for further study. Euthanasia, fixation, embedding, sectioning, staining, and other demanding techniques are described. The book also deals with two very important specialized sampling methods: bronehioalveolar lavage and blood collection.