From 1984 to 1989 the clinicopathological aspects of 21 patients with smooth muscle tumours of the stomach were reviewed. Ten patients had leiomyomas: 7 males, 3 females, average age 53 +/- 8 years. Four out of seven leiomyomas presenting with haematemesis were diagnosed correctly by an endoscopist but biopsy was positive in only two patients. Three leiomyomas were found incidently at laparotomy, and a total of nine leiomyomas were resected with a cuff of normal stomach. Their size ranged from 2 to 20 cm. All patients who underwent local resection are alive. Eight patients had leiomyosarcomata: 3 males, 5 females, average age 62 +/- 9 years. Six of these patients had an epigastric mass and four had haematemesis or melaena. The remaining patient in this group presented with dysphagia. Seven of these patients, who had no evidence of metastatic disease, underwent exploratory laparotomy. In four, palliative resections of the stomach and distal oesophagus were performed. In two, exogastric lesions involving colon and liver respectively were resected en bloc with a cuff of stomach. In one, biopsy alone was carried out. Two patients in this group are alive 1 and 2 years following surgery. Adjuvant treatment was not given to any of our patients. The remaining three tumours comprised a smooth muscle tumour of undetermined malignant potential whose clinical behaviour was unpredictable, and two leiomyoblastomas which mimicked malignant tumours in their presentation.