Selection of appropriate chemotherapy, including identification of platinum resistance, is critical to effective management of advanced epithelial ovarian cancer (EOC). ChemoFx®, a multiple treatment marker (chemoresponse assay), has been developed to address this challenge and to improve outcomes in patients with advanced EOC. While much work has been done that has demonstrated the analytical validity of this assay, more recent studies have highlighted the unique clinical benefits offered by the assay. A prospective, multicenter trial has shown an increase in overall survival (OS) of 14 months and an increase in progression-free survival (PFS) by 3 months in patients with recurrent EOS treated by a “sensitive” therapy based on ChemoFx results. Along with other studies showing similar gains in OS and PFS, ChemoFx has been shown to be both a prognostic and predictive marker in patients with recurrent EOC where current treatment options are sorely lacking. In addition to these clinical benefits, economic analyses have shown that ChemoFx is a cost-effective intervention. Current guidelines and technology assessments relating to ChemoFx are largely outdated and refer primarily to metrics of analytical validity. Thus, in addition to analytical validity, the clinical validity, clinical utility and economic impact of ChemoFx are reviewed herein, including published literature, technology assessments by independent parties, and regulatory approvals of this marker.