There is epidemiological evidence that high-density lipoprotein (HDL) concentrations, or HDL "levels," exert protection from atherosclerosis, suggesting that HDL plays a role in vascular diseases. More accurate measures of HDL "function" are emerging, such as HDL efflux assays, which measure removal of cholesterol from peripheral tissues. Using this assay, we have demonstrated that psoriasis is associated with decreased HDL "levels" and HDL "function." The study by Holzer et al. in this issue demonstrates in an open-label, uncontrolled study that HDL function is impaired in psoriasis and improves after successful treatment of psoriasis. These findings underscore the notion that treatment of psoriasis likely extends beyond the skin and that a randomized controlled clinical trial is needed to confirm these findings.