Recebido em 6/3/09; aceito em 30/7/09; publicado na web em 11/1/10 AIR POLLUTION AND EMERGENCY ADMISSIONS FOR CARDIORESPIRATORY DISEASES IN LISBON (PORTUGAL). Daily records of hospital admissions due to cardiorespiratory diseases and levels of PM 10 , SO 2 , CO, NO, NO 2 , and O 3 were collected from 1999-2004 to evaluate the relationship between air pollution and morbidity in Lisbon. Generalised additive Poisson regression models were adopted, controlling for temperature, humidity, and both short and long-term seasonality. Significant positive associations, lagged by 1 or 2 days, were found between markers of traffic-related pollution (CO and NO 2) and cardiocirculatory diseases in all age groups. Increased childhood emergency admissions for respiratory illness were significantly correlated with the 1-day lagged SO 2 levels coming from industrial activities.