Multiple pleural biopsies (up to 10) were taken with the Abrams needle through a single aspiration site in 55 patients with pleural effusions. A definite positive or suggestive pleural biopsy diagnosis was made in 33 patients (60%). In 32 of the 33 patients the pathological abnormality was confined to only a proportion of the biopsies. Pleural biopsies were positive or suggestive in 26 out of 36 patients (72%) eventually shown to have tumour and seven out of eight patients (88%) with tuberculosis. Small pneumothoraces occurred in four patients and surgical emphysema in two.