The determination of site of care is an essential decision in the management of patients with community-acquired pneumonia (CAP). Patients with mild to moderate CAP may be safely treated at home. Instead, those patients with severe pneumonia must be hospitalized to assure an effective treatment. Severity of CAP is associated with mortality that depends both on the patient's frailty and the intensity of lung inflammation. Because there is no single predictor factor to assess prognosis, diverse, prediction rides have been developed to establish severity of CAP and guide the decision of site of care. in our country a new prediction ride, derived from hospitalized patients that incorporate simple clinical variables has been developed. However, this rule requires to be validated in the ambulatory setting before wide spread use is suggested. Prediction rules are objective and relatively accurate models to assess prognosis that may aid clinicians to evaluate patient's risks and to improve hospitalization decisions, Nevertheless, although the prediction rides may guide the initial management of patients with CAP, they are not intended to replace the clinical judgment, which remains as the "art of medicine".