Given the extensive emphasis on developing more effective systems of care for patients with HBP, the writ- ing committee also feels it is important to present a new concept of structural measures, which are designed to improve these systems. This category of quality measure is intended to evaluate care at the aggregate care deliv- ery unit (CDU) level, as opposed to the performance and quality measures, which are designed to summarize the evaluation of care of prespecified populations with HBP at the individual, group clinician, or health plan levels. A CDU represents the organizational structure of the clinicians who are delivering care to these patients. This measurement includes a hierarchical scale of the health delivery infrastructure for optimal management of patients with HBP that is available to organizations such as a small medical practice, a multispecialty clinic, a community-based health center (eg, a Federally Quali- fied Health Center), a hospital-owned ambulatory care site, or even a large, geographically dispersed health system (eg, the US Department of Veterans Affairs). Figure 1. Performance of HEDIS Controlling HBP Measure 1999 2017 (percent of patients with hypertension treated in accordance with the HEDIS Controlling HBP Measure). The HEDIS Hypertension Measure6 assesses adults 18 85 years of age who had a diagnosis of hypertension and whose blood pressure was adequately controlled according to the following criteria: 1) Adults 18 59 years of age whose blood pressure was <140/90 mmHg. 2) Adults 60 85 years of age, with a diagnosis of diabetes mellitus, whose blood pressure was <140/90 mmHg. 3) Adults 60 85 years of age, without a diagnosis of diabetes mellitus, whose blood pressure was <150/90 mmHg (likely to be lowered in 2018 to <140/90 mmHg). 