Substantial progress has been made recently in the development of nonpeptide angiotensin II receptor antagonists, a goal that has long remained an unmet challenge. Pieter Timmermans and colleagues review the pharmacology and the course of events that led to the identification of the lead compound and clinical candidate DuP753. Nonpeptide angiotensin II receptor antagonists represent novel therapeutic agents and are the preferred probes for exploring the (patho)physiological role(s) of angiotensin II. In addition, these compounds have provided evidence for the existence of different binding sites/receptors for angiotensin II.