The ACC/AHA Task Force on Clinical Practice Guide- lines strives to ensure that the guideline writing com- mittee includes requisite expertise and is representative of the broader medical community by selecting experts from a broad array of backgrounds, representing dif- ferent geographic regions, sexes, races, ethnicities, intellectual perspectives/biases, and scopes of clinical practice. The ACC and AHA have rigorous policies and methods to ensure that documents are developed with- out bias or improper influence. The complete policy on relationships with industry and other entities (RWI) can be found online. Beginning in 2017, numerous modifications to the guidelines have been and continue to be implemented to make guidelines shorter and enhance user friendli- ness. Guidelines are written and presented in a modu- lar knowledge chunk format, in which each chunk in- cludes a table of recommendations, a brief synopsis, recommendation-specific supportive text and, when appropriate, flow diagrams or additional tables. Hyper- linked references are provided for each modular knowl- edge chunk to facilitate quick access and review. More structured guidelines including word limits ( tar- gets ) and a web guideline supplement for useful but noncritical tables and figures are 2 such changes. This Preamble is an abbreviated version, with the detailed version available online. Patrick T. O Gara, MD, MACC, FAHA Chair, ACC/AHA Task Force on Clinical Practice Guidelines Although there has been substantial improvement in atherosclerotic cardiovascular disease (ASCVD) outcomes in recent decades, ASCVD remains the leading cause of morbidity and mortality globally.S1-1 S1-3 In the Unit- ed States, it is also the leading cause of death for peo- ple of most racial/ethnic groups, with an estimated cost of >$200 billion annually in healthcare services, medications, and lost productivity. 