The study is designed to determine whether an accelerated course of hypofractionated radiation therapy with daily image guidance and motion assessment/control will allow more effective treatment of poor performance status patients with stage II-III NSCLC, who would benefit from local therapy compared to standard radiation therapy (60 Gy in 2 Gy per fraction). Poor performance status patients can be a heterogeneous group, with tumor-related factors, other co-morbidities, or advanced age placing patients in the category. These patients have traditionally been underrepresented in clinical trials, and thus no prospective study has evaluated the efficacy of other radiotherapy dose fractionations in these patients. One phase III trial of "poor-risk" locally advanced NSCLC (RTOG 93-04) included just over 40% Karnofsky performance status 60-70 patients and showed median survival times of 9.5 and 10.3 months with 60Gy of conventional radiation therapy alone or with recombinant β-interferon [18]. 1 year overall survival was just 44% in these patients.