Daytime office blood pressure measurements (OBPM), still recommended and utilized today for diagnosis and management of hypertension and categorization of cardiovascular disease (CVD) risk, fail to reveal clinically important features of the mostly predictable BP 24 h pattern and leads to a large proportion of individuals being misclassified. Most clinical guidelines now recommend ambulatory BP monitoring (ABPM) be applied to adult patients to confirm the OBPM-based diagnosis of hypertension, based on the high prevalence of masked hypertension and masked normotension plus demonstrated significantly better CVD prognostic value of around-the-clock ABPM than daytime OBPM. Nonetheless, there is yet no consensus of which parameter(s) and ABPM thresholds to utilize to diagnose hypertension. Findings of large prospective ABPM-based CVD outcome trials permit prospective evaluation of treatment and other induced changes in OBPM and ABPM during follow-up on CVD risk by incorporating multiple periodic (at least annual) patient ABPM assessments. They indicate: 1) asleep systolic BP (SBP) mean and sleep-time relative SBP decline (dipping) together are the most significant and only BP-derived prognostic markers of CVD risk; accordingly, around-the-clock ABPM should be the recommended method to diagnose true arterial hypertension and accurately assess CVD risk; and (2) treatment-induced lowering of the asleep SBP mean and rise of the sleep-time relative SBP decline towards the normal dipper BP pattern are both significantly protective against CVD events, thus constituting novel therapeutic targets to substantially better reduce CVD risk compared to the traditional approach that targets control of daytime OBPM or awake BP mean.