This issue of Critical Care Clinics, guest edited by Drs. Hernando Gomez Danies and Joseph Carcillo, focuses on Coagulation/Endothelial Dysfunction. This is one of four issues each year selected by the series consulting editor, Dr. John Kellum. Articles in this issue include, but are not limited to: Cell-cell communication breakdown and endothelial dysfunction; Role of the Tie2/Angiopoetin pathway in endothelial dysfunction; The Glycocalyx; Platelet activation and endothelial dysfunction; Role of antithrombin III and tissue factor pathway; Red blood cell dysfunction; Microvascular hemodynamics, autoregulation and mechanotransduction control of blood flow distribution; Nitric oxide and endothelial dysfunction; Microvascular dysfunction; Hemolytic Uremic Syndrome and atypical HUS; Thrombotic thrombocytopenic purpura, Heparin induced thrombocytopenia and Disseminated intravascular coagulation in the critically ill; Thrombocytopenia associated multiple organ failure (TAMOF); Meningococcemia; Immune consequences of endothelial dysfunction during sepsis; Therapeutic targets in thrombotic microangiopathies with a focus on endothelial disorders; and Coagulation disorders in HLH/Macrophage activation syndrome.