Chronic obstructive pulmonary disease - COPD, being one of the most frequent chronic pathologies in the world, an important number of such patients can necessitate, at a certain moment, a thoracic surgical intervention, especially pulmonary resections for pulmonary carcinoma. In these cases, the removing of a certain volume of pulmonary tissue from a patient who already has a respiratory malfunction necessitates a judicious preoperative evaluation to establish the correct indication, risk factors and postoperative prognosis (at least regarding the pulmonary function). Although the preoperative evaluation for pulmonary resections has been studied for many years, a parameter has not been found yet, simple or combined, to accurately predict the outcome. The majority of the candidates for pulmonary resections can be operated without previous complicated tests like CPET (cardio-pulmonary exercise testing) and regional pulmonary function, which are expensive and sometimes non accessible. In the past years, CPET gained more and more field in the appreciation of the surgical risk; combined with the split measurement of the function of the two lungs, it can even predict the postoperative effort capacity. In the complex preoperative evaluation of the chronic pulmonary patients we must not forget other, not so obvious aspects, so that the patient could benefit by the optimum moment and health status for his or her operation, for the purpose of a better prognosis.