Hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome has been recognized as a complication of preeclampsia-eclampsia for decades. Recognition of this syndrome in women with preeclampsia is increasing because of the frequency of blood test results that reveal unexpected thrombocytopenia or elevated liver enzymes. The diagnosis of HELLP syndrome requires the presence of hemolysis based on examination of the peripheral smear, elevated indirect bilirubin levels, or low serum haptoglobin levels in association with significant elevation in liver enzymes and a platelet count below 100,000/mm(3) after ruling out other causes of hemolysis and thrombocytopenia. The presence of this syndrome is associated with increased risk of adverse outcome for both mother and fetus. During the past 15 years, several retrospective and observational studies and a few randomized trials have been published in an attempt to refine the diagnostic criteria, to identify risk factors for adverse pregnancy outcome, and to treat women with this syndrome. Despite the voluminous literature, the diagnosis and management of this syndrome remain controversial. Recent studies suggest that some women with partial HELLP syndrome may be treated with expectant management or corticosteroid therapy. This review will emphasize the controversies surrounding the diagnosis and management of this syndrome. Recommendation for diagnosis, management, and counseling of these women is also provided based on results of recent studies and my own clinical experience.