The patient with an asymptomatic pelvic mass is a well-recognised clinical presentation in gynaecology. Masses may be physiological (e.g. pregnancy), representing benign conditions, ovarian tumours or fibroids, or be an indication of pelvic malignancy. It is this last group that causes most concern. The aim of the nationwide centralisation of gynaecological oncology services is survival improvement for patients with gynaecological cancer. For this to be effective it is essential that the gynaecologist is able to carefully assess the patient presenting with a pelvic mass, identifying those likely to have pelvic cancer. Establishing the likely diagnosis aids appropriate decision making regarding how the patient is managed and who delivers the care. This article will describe the assessment of the patient, techniques used to investigate, and therapeutic options for the patient presenting with a pelvic mass.