Biopsies of 150 consecutive suspected lung cancers were performed with fine needles having circumferentially beveled tips that produced cytology and tiny tissue cores suitable for histology. Visible tissue cores were aspirated in 92% (n = 138) and histologic diagnoses were obtained in 72% (n = 108). There were 118 (79%) proven malignant and 27 (18%) proven benign lesions. Sensitivity and specificity of cancer diagnoses were 97% and 100%, respectively. Biopsy histology was the only positive cancer specimen in two biopsies (1.7%). Biopsy cytology was the only positive cancer specimen in 20 cases (17.2%). Biopsy cytology and histology agreed with the proven cell type in 71.8% and 78.6% of cancers, respectively. As expected, when large-cell undifferentiated carcinoma was regarded as a nonspecific cell type consistent with either poorly differentiated adenocarcinoma or poorly differentiated epidermoid carcinoma, biopsy-cell-type accuracy increased greatly. Specific benign diagnoses were obtained in 44% of the 27 biopsies of proven benign lesions: cytology (four), core histology (five), and bacteriology (nine). Simple and complicated pneumothorax occurred in 10% and 4% of biopsies, respectively. It was concluded that biopsy with fine, circumferentially beveled needles can produce useful histology to supplement biopsy cytology.