The purpose of this review is to integrate information available regarding pseudohypertension. A MEDLINE search (1966 to December 1993) was conducted using the key words pseudohypertension and Osler's maneuver. All articles containing reference to pseudohypertension were selected and reviewed. Additional articles were obtained from the citations included within these articles. Quantitative information from each reference was reviewed to derive qualitative statements about new perspectives on the pathophysiology and evaluation of pseudohypertension. The prevalence of pseudohypertension is unknown but probably increases with advancing age. Diagnosis requires a high index of suspicion. Demographic information has not been shown to be useful for identifying patients with pseudohypertension. Symptoms of postural hypotension despite antihypertensive therapy, treatment-resistant hypertension, and the absence of end-organ effects in long-standing "hypertension" are clinical features that suggest pseudohypertension. Automatic infrasonic blood pressure measurements may offer more accurate estimates of intra-arterial blood pressure than indirect sphygmomanometry in patients with these clinical features.