BACKGROUND Lung cancer remains a leading cause of cancer-related mortality in North America. Despite potentially curative resection, non-small cell lung cancer (NSCLC) patients remain at high risk of relapse and death, with a 5-year survival rate of less than 67%. Several randomized trials now confirm a survival benefit with adjuvant platinum-based chemotherapy seen in the NSCLC Collaborative Group meta-analysis, including the International Adjuvant Lung Trial, National Cancer Institute of Canada BR.10, and Adjuvant Navelbine International Trialist Association (ANITA) trials, with absolute improvements in 4- and 5-year survival rates of 4% to 15%. This study examines whether referral patterns for adjuvant therapy in NSCLC have changed since the presentation of confirmatory trials. METHODS Retrospective chart review was undertaken at a major tertiary care center, identifying patients with completely resected stages I-IIIA NSCLC from May 2003 to May 2005. RESULTS A total of 204 patients were identified (59 IA, 77 IB, 8 IIA, 41 IIB, and 19 IIIA). Institutional policy before May of 2003 was not to administer adjuvant therapy outside a clinical trial. After presentation of the International Adjuvant Lung Trial in May 2003, 31% (36/115) of patients with completely resected NSCLC from May 2003 to May 2004 were referred for adjuvant chemotherapy. After presentation of the BR.10 and Cancer and Leukemia Group B 9633 results in June 2004, 63% (56/89) were referred between June 2004 and May 2005. Reasons for not referring to a medical oncologist included stage IA disease, surgeon thought adjuvant therapy inappropriate, patient declined, comorbidities, postoperative complications, and advanced age. Of 92 patients referred to medical oncology, 42 (46%) received adjuvant chemotherapy. Reasons for not prescribing adjuvant chemotherapy included patient refusal (50%), comorbidities (14%), stage IA (10%), and advanced age (4%). Vinorelbine/cisplatin was the regimen most commonly used (67%). CONCLUSIONS The presentation of positive adjuvant therapy trials in NSCLC has changed clinical practice substantially, doubling the number of patients with completely resected NSCLC referred for adjuvant chemotherapy since May 2004 (31% versus 63%). Although new evidence to support adjuvant chemotherapy in lung cancer is being disseminated to and accepted by physicians, more patient education and decision support may be required to increase uptake of adjuvant therapy in the early stage NSCLC population.