Detection of a second primary at the time of initial work-up of patients with head and neck cancers has an important bearing on management planning. In a 12-month period, a series of 105 patients with an index head and neck primary (skin malignancies excluded) of the squamous cell type were subjected to the following screening procedure. Under topical anesthesia, with the patient in the sitting position, a small-size flexible bronchofiberscope (Olympus B3R) was introduced through the nose. As the scope was advanced, the nasal cavity, nasopharynx, oropharynx, hypopharynx, and larynx were examined. The tracheobronchial tree was also examined if the chest x-ray showed abnormal findings. The endoscope was then passed down to examine the esophagus, with oxygen insufflated via the biopsy channel at a rate of 1 liter per minute. The index primary sites included the tongue (20), alveolus (7), floor of mouth (2), palate (4), buccal mucosa (3), hypopharynx (17), and larynx (52). There was little patient discomfort and no complication. Nine patients (8.5%) were found to have simultaneous primary tumors including two patients with triple primaries and one with quadruple lesions. The additional tumors were in the following sites: esophagus (6), tonsil (2), floor of mouth (1), nasopharynx (1), bronchus (1), palate (1), and oropharynx (1). The treatment plans were changed in all nine patients with the discovery of multiple tumors. It is concluded that the panendoscopic screening in the manner described is simple, safe, and convenient and the information is contributory to treatment planning.