This pilot project was designed to identify individuals at high risk for lung cancer in a family practice clinic setting, and to detect lung cancer in this high-risk group. Patients visiting their primary care physician in a busy 15-doctor outpatient clinic were asked to complete a simple one-page questionnaire designed to identify those at high risk for lung cancer (age > 50 years, smoker > 30 pack-years, or worrisome family history or occupational exposure). Simple spirometry was performed on these high-risk patients, and those showing airflow obstruction (FEV1 < 70% predicted, FEV1/FVC ratio < 0.70) were asked to participate in screening studies. Screening studies consisted of two-view chest radiography, noncontrast chest CT scan, and induced and spontaneous sputum cytology studies. Details of patient visits to primary care physicians from January 1, 2001, through December 31, 2001, are as follow: total visits, 52,336; patients > 50 years old, 14,159 visits; total questionnaires completed, 1,296; patients qualifying for spirometry, 430; patients eligible for screening based on abnormal spirometry findings, 126; and patients screened for cancer, 88. Five of these 88 screened patients (5.7%) showed lung cancer, 4 on the initial examination, and 1 on follow-up testing. Cancers were detected by cytology only (n = 1); CT scan only (n = 1); CT scan and radiograph only (n = 2); and CT scan, radiograph, and cytology (n = 1). Cell types included two squamous cell carcinomas and two adenocarcinomas, and one patient had multiple lesions (adenocarcinoma and squamous cell carcinoma). The mean patient age was 68 years (range, 62 to 82 years) for the two women and three men. All patients have received treatment and are alive. Screening costs for the four patients with cancer detected on the initial examination totaled $12,900 per patient. In conclusion, lung cancer can be detected in high-risk asymptomatic individuals in a busy primary care medical practice, using readily available diagnostic procedures.