Recurrent pneumonia is still an important problem. In this retrospective study we reviewed the records of 90 patients with a history of 3 or more episodes of acute pneumonia. The 90 patients accounted for altogether 347 episodes of acute pneumonia, treated at the Department of Infectious Diseases, Lund. 12 patients died while being treated for pneumonia at the department. Pneumonia alone caused the death in 7 of these 12 patients. In all, 51 of the patients died during the 11-year study period. Death certificates, stating the cause of death, were available in 38 cases, and pneumonia was the direct cause of death in 15 patients. Most of the infections were community-acquired, only 47 were nosocomial, 20/90 patients suffered from disorders associated with immune deficiency, and 70 patients had other predisposing illnesses. We found a larger number of underlying immunoglobulin deficiencies (11 patients of 38 investigated) than previously reported. Of 13 patients without other known, predisposing conditions, hypogammaglobulinemia was found in 3 patients. We suggest that patients with recurrent pneumonia should be thoroughly investigated, in order to find previously unrecognized immune deficiency.