It is very important to note that safe and effective treatment of recurrent or persistent pneumonia in children is based on firmly establishing an etiologic diagnosis. Empiric treatment using repeated courses of antibiotics and hope is unlikely to yield cure or even good control of most of these processes and is likely to result in more cost to the patient's health and pocketbook. Applied in a staged and systematic way, the diagnostic tools currently available should enable the clinician caring for children to diagnose most of their patients with recurrent or persistent pneumonia. Consultation with a pediatric pulmonologist will generally speed the process and help with difficult or confusing cases. Because effective therapy is available but differs greatly from one etiology to another, early accurate etiologic diagnosis is extremely important. The prognosis for those with asthma generally is very good. But, delay in diagnosis of other causes of recurrent or persistent pneumonia can lead to irreversible pulmonary structural damage that ultimately can only be treated by lung transplantation, if at all.