Solitary fibrous tumours are unusual mesenchymatous tumours, most often found on the pleura. The authors report five cases hospitalised between 1998 and 2003. With the greatest occurrence in the fifth decade, they are often accidentally found but sometimes associated with a paraneoplastic syndrome such as refractory hypoglycaemia. The diagnosis is based on computed tomography and complete surgical resection is the best treatment. Adjuvant therapy is proposed for the histologically aggressive forms. Because of the possibility of local or distant recurrence and malignant transformation, long-term monitoring is strongly recommended.