['To evaluate the effects of an intensive postoperative physiotherapy program focused on respiratory exercises in patients undergoing lobectomy by open thoracotomy.', 'Quasi-experimental study.', 'Tertiary referral academic hospital.', '208 patients undergoing lobectomy by open thoracotomy.', 'Control group patients (n=102) received standard medical/nursing care, and experimental group patients (n=106) added to the standard clinical pathway a daily physiotherapy program focused on respiratory exercises until discharge.', 'Analyzed outcomes were the frequency of postoperative pulmonary complications (PPCs) more amenable to physiotherapy (pneumonia, atelectasis and respiratory insufficiency) and length of hospital stay (LOS).', 'Both groups were comparable regarding preoperative and surgical characteristics. Incidence of PPCs was 20.6% in control and 6.6% in experimental group (P=.003). Median (IQR) LOS in control group was 14 (7) days (Huber M estimator 14.21) and 12 (6) days (Huber M estimator 12.81) in experimental. Logistic regression model identified the evaluated physiotherapy program (P=.017; EXP [B] 95% CI 0.081-0.780) and % FEV1 (P=.042; EXP [B] 95% CI 0.941-0.999) as protective factors for the development of PPCs in patients undergoing lobectomy.'] Do postoperative Respiratory Exercises Reduce the Risk of Developing Pulmonary Complications in Patients Undergoing Lobectomy?