Because a highly sensitive and specific serum marker for ovarian carcinoma has not been reported, it is unlikely that there will be an application of serum markers for screening for this disease in asymptomatic women. However, many oncologists use serum tumor markers initially to differentiate epithelial ovarian carcinoma from benign gynecological conditions prior to surgery, so as to ensure appropriate surgical referral, and then to monitor the clinical course of disease during and after adjuvant therapy. The most commonly performed tumor marker assay in ovarian cancer (CA125) has been extremely valuable in patient management, but this marker is also elevated in a considerable proportion of patients with benign gynecologic diseases and endometriosis, and a relatively small proportion of patients with early stage disease. A new class of serum tumor markers, the highly glycosylated, high molecular weight mucins, have enormous potential in the management of ovarian cancer patients, since the use of assays for these markers may overcome many of the problems associated with CA125. Indeed, when used in combination with CA125, some mucin-based assays have increased the sensitivity and specificity of detection, thereby eliminating many false positive results seen with patients with benign disease and endometriosis, and also predicted disease recurrence in the majority of patients before clinical symptoms became apparent. These markers are the subject of this review, with particular attention to the commercially-available mucin-based assays.