High-resolution computed tomography (HRCT) as a tool for investigation of bronchovascular and pulmonary responses to various physiologic and pharmacologic stimuli is a new field of application. The potential of this method has only recently been investigated in animal experiments. To date, research has focused on the determination of airway responses in the context of agonist challenge such as aerosolized or i.v. histamine, isotonic saline, halothane anesthesia, and hypoxia. Likewise, physiologic HRCT has been used in the elucidation of the pulmonary circulatory response to acute hypervolemia and hypoxia. Early results indicate that significant observations can be derived from HRCT as it is the only existing method that not only detects physiologic responses but, unlike existing methods, can characterize their site and locoregional differences. In this article, the rationale for and present status of physiologic HRCT is presented.