Malignant small bowel tumours are rare, with about 320 deaths every year due to metastases. Tumours of differing histologic entitites (adenocarcinomas, leimyosarcomas, non-Hodgkin, lymphomas, carcinoids) are detected at late stages of the disease because of non-specific symptoms. Valuable diagnostic means are small bowel enema, intestinoscopy and abdominal CT/ultrasound. Five-year survival rates are poor for carcinomas (21%), for sarcomas (37%), lymphomas (44%) and best for carcinoids (100%). Surgical options are poor for carcinomas with a high number of R2 resections and bypass operations. Multivisceral surgery is beneficial for sarcomas and lymphomas, followed by local radiation therapy or chemotherapy.