Patients with SCLC should have a complete history and physical examination with particular attention paid to symptoms and signs of extensive disease and paraneoplastic syndromes. Hematology and biochemistry should be obtained at the initial assessment. A chest radiograph will usually have been performed prior to diagnosis. Further imaging should then be done to determine if the patient has limited or extensive disease. In the nonprotocol setting, extensive radiologic investigations are not required once a site of metastatic disease has been identified. If symptoms or signs are present to indicate a site of extensive disease, then this should direct the next test. In the absence of any specific findings then either bone scan or abdominal imaging with either US or CT scanning may be done based on the roughly equal likelihood of metastatic disease in liver or bone. Because a bone scan is less expensive, it is often the next test selected. If the bone scan is negative, abdominal imaging should then be performed, followed by brain CT scan. If these investigations are negative, the next study should be a thoracic CT scan. Bone marrow examination is probably unnecessary in the nonprotocol setting unless serum LDH levels are elevated. In the setting of a clinical trial, complete staging should be done and even more precise staging using the TNM system should be considered based on the improved survival of patients with proven stage I disease. Using more precise staging will allow accurate comparisons of clinical trials and eliminate or minimize the question of patient selection. Surgical staging with mediastinoscopy may come to have a role in accurately determining stage I or II disease.