This study will evaluate the efficacy and safety of neoadjuvant chemotherapy with gemcitabine and pemetrexed given together 4-times biweekly in patients with resectable NSCLC. All patients will be seen by members of the Thoracic Oncology Program at the H. Lee Moffitt Cancer Center and Research Institute in Tampa, Florida, and they will be discussed in our weekly multidisciplinary thoracic oncology conference. The conference includes pathologists, radiologists, thoracic surgeons, pulmonologists, radiation oncologists, medical oncologists, oncology nurse specialists, case managers, social workers, and clinical trials coordinators. They will have initial tests as outlined in the study timetable. Patients will receive gemcitabine biweekly on days 1, 15, 29, and 43 at a dose of 1,500 mg/m2. They will also receive pemetrexed at a dose of 500 mg/m2 on days 1, 15, 29, and 43. Gemcitabine will be given first over a period of 30 minutes i.v. followed by pemetrexed over 10 minutes i.v. All patients will get a post induction chemotherapy PET scan, CT scan, and PFT's including a DLCO. They will then go on to thoracotomy including bronchoscopy and mediastinal lymph node dissection between days 64 and 77 if the tumor is deemed completely resectable on restaging studies.