Chlamydia and Legionella are recognized causes of atypical pneumonia. A case of pneumonia due to Chlamydia psittaci/TWAR and Legionella bozemanii following renal transplantation is described. Legionella bozemanii infection was diagnosed by a rise in antibodies and by isolation of the organism from bronchoscopy specimens. It is unusual to find pneumonia caused concomitantly by two such agents. This case, despite the fatal outcome, emphasises the necessity for a comprehensive approach to the diagnosis of atypical pneumonia, including culture for Legionella, especially in immunocompromised patients.