With the advent of noninvasive 24-hour ambulatory blood pressure monitoring (ABPM), clinicians have access to a wealth of individualized data for the hypertensive patient. This has led to a greater understanding of the pathophysiology of hypertension and its complications. This tool has provided more precise diagnostic criteria for hypertension and helped discover those with white coat and masked hypertension. Patterns noted on ABPM and correlated with outcomes have allowed for more accurate identification of patients at high risk of cardiovascular (CV) events, and have offered an additional prognostic tool. In addition, ABPM allows for the assessment of the efficacy and adequacy of blood pressure treatment. In the current paper, we will describe the essential components of ABPM, review the evidence detailing the prognostic information that can be derived from its use, highlight clinical scenarios wherein ABPM can offer invaluable diagnostic information, and describe applications of ABPM that evaluate the efficacy of treatment of the hypertensive patient.