On the basis of our own experience the importance and usefulness of the scalene-node-biopsy for the diagnosis of intrathoracic diseases will be reported. If there is no positive histological result in the obtained lymph nodes during surgery, one can continue with the mediastinoscopy (Carlens) without aggravating Daniels biopsy. The scalene-node biopsy is a short surgical procedure, that can easily be done in local anaesthesia. A positive lymph node makes mediastinoscopy or a following thoracotomy unnecessary. Especially in sarcoidosis, systemic diseases (malignant lymphomas) and silicosis biopsy yields good results.