A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was: does video-assisted thoracic surgery provide a safe alternative to conventional techniques in patients with limited pulmonary function who are otherwise suitable for lung resection? Altogether, more than 280 papers were found using the reported search, of which 7 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. One of the largest studies reviewed was a retrospective review of the Society of Thoracic Surgeons database. The authors compared 4531 patients who underwent lobectomy by video-assisted thoracic surgery (VATS) with 8431 patients who had thoracotomy. In patients with a predicted postoperative forced expiratory volume in 1 s (ppoFEV1%) of <60, it was demonstrated that thoracotomy patients have markedly increased pulmonary complications when compared with VATS patients (P = 0.023). Another study compared perioperative outcomes in patients with a ppoFEV1% of <40% who underwent thoracoscopic resection with similar patients who underwent open resection. Patients undergoing thoracoscopic resection as opposed to open thoracotomy had a lower incidence of pneumonia (4.3 vs 21.7%, P < 0.05), a shorter intensive care stay (2 vs 4 days, P = 0.05) and a shorter hospital stay (7 vs 10 days, P = 0.058). A similar study compared recurrence and survival in patients with a ppoFEV1% of <40% who underwent resection by VATS or anatomical segmentectomy (study group) with open resection (control group). Relative to the control group, patients in the study group had a shorter length of hospital stay (8 vs 12 days, P = 0.054) and an improved 5-year survival (42 vs 18%, P = 0.02). Analysis suggested that VATS lobectomy was the principal driver of survival benefit in the study group. We conclude that patients with limited pulmonary function have better outcomes when surgery is performed via VATS compared with traditional open techniques. The literature also suggests that patients in whom pulmonary function is poor have similar perioperative outcomes to those with normal function when a VATS approach to resection is adopted.