An empyema is a collection of fluid generally due to infection. The collections can form in the chest cavity between the lung and chest wall. Until 2009, at Miller Children's Hospital treatment for pediatric empyemas was individually decided, based on recommendations from medical and surgical subspecialists. In an attempt to improve outcomes, a treatment algorithm based on literature review and analysis of previous experience, was put in place starting October 2009. This study is a retrospective chart review comparing outcomes from patients treated prior to 2009 versus those patients treated based on the algorithm from October 2009 - October 2011. Patient outcomes and length of hospital stay will be evaluated.