The contrast agent Iotrolan 300 has potential advantages for bronchography over previous agents in that it can be injected directly through the bronchoscope and it does not obscure bronchoscopic vision or interfere with further bronchoscopic procedures. It was used for selective bronchography in 20 patients with suspected bronchiectasis. Side effects and change in FEV1 and in arterial oxygen saturation were compared in these patients and in 14 patients undergoing bronchoscopy for suspected carcinoma. Thirteen of the 20 patients undergoing bronchography had side effects, mainly headache, nausea, and a feeling of heat or flushing. The fall in FEV1 at four hours (0.3 l) did not differ from the fall in the control group (0.1 l). The fall in arterial oxygen saturation (SaO2) during bronchography (9.4%) did not differ significantly from the fall during bronchoscopy in the control group (6.1%). Iotrolan gave good quality bronchograms, which in all cases provided a diagnosis. Iotrolan appears to be suitable for bronchography by fibreoptic bronchoscope and to be well tolerated.