Gestational trophoblastic neoplasia (GTN) comprises a spectrum of related conditions, all of which are characterised by low incidence and high cure rates. Placental site trophoblastic tumours (PSTT) are the rarest form of GTN and can complicate any form of conception but most frequently follow a normal pregnancy. Choriocarcinoma can present with extremely varied symptoms and signs associated with the differing sites of metastatic disease and occur at a wide range of time after the causative pregnancy. For most women with GTN following a recent molar pregnancy, the investigations performed before chemotherapy treatment are limited to a Doppler ultrasound of the pelvis and a chest X-ray. The use of routine first-trimester ultrasound combined with effective follow-up programmes has produced near 100% cure rates for women following molar pregnancies. Optimising molar pregnancy follow-up services and education of clinicians to GTN in women with cancer are most important to produce effective patient care.