Metastasis from epithelial ovarian cancer can occur via the transcoelomic, haematogeneous, or lymphatic route. Of these, transcoelomic metastasis is the most common, and is responsible for the greatest morbidity and mortality in women with this disease. Unfortunately, very little is known about the mechanisms behind this process. This review assesses the current evidence and ideas about the biology of transcoelomic dissemination. The mechanisms of cell detachment, migration, and implantation in transcoelomic metastasis are placed within the context of clinical observations of ovarian cancer to derive a stepwise hypothesis of this process. Evidence for transcoelomic dissemination versus transcoelomic metaplasia in ovarian cancer is presented. Future high throughput microarray studies that compare changes at a genomic and gene expression level between primary ovarian tumours and their peritoneal metastases are hoped to lead to a more conclusive picture of transcoelomic metastasis, and to delineate the key molecular players in this process. These studies might also result in the identification of potential new therapeutic targets in ovarian cancer.