Since ambulatory blood pressure monitoring (ABPM) became feasible, around-the-clock data have been collected in health and disease by an international team of investigators within the scope of the project on the BIOsphere and the COSmos (BIOCOS). The derivation of time-specified reference values in health, qualified by gender, age, and whenever possible, ethnicity, led to the definition of Vascular Variability Disorders (VVDs), abnormal patterns of blood pressure and/or heart rate variability. Outcome studies documented their association with an increased cardiovascular disease risk. These results served as the foundation for a consensus document agreed upon at the October 6, 2008, meeting held at St. Anna Hospital, Masaryk University, Brno, Czech Republic. Much added data have accumulated since then. In their light, herein we review evidence underlying the need for 7-day/24-hour ABPM and for their chronobiologic interpretation (C-ABPM).