We have developed a CRP-guided management algorithm based on recent studies in which the accuracy of CRP for identifying patients with pneumonia was confirmed.(10;11) Importantly, these 2 studies each confirmed that CRP levels provide additional diagnostic support beyond that gained from application of clinical prediction rules. In the proposed study, we will recommend that physicians first assess the probability of pneumonia based on clinical findings, in accordance with current practice recommendations as follows: 1) Low Clinical Suspicion (<5% probability of pneumonia): Absence of fever (T>38C), tachycardia (HR>100), or tachypnea (RR>24), and normal chest examination. These patients should receive symptomatic therapy, and do not require CXR or antibiotic treatment; 2) High Clinical Suspicion (>30% probability of pneumonia): At least 1 abnormal vital sign and abnormal chest examination. These patients receive CXR and antibiotics based on CXR findings or high clinical suspicion; 3) Intermediate Clinical Suspicion (5-30%): All others. Current practice guidelines recommend considering CXR in these patients, however no further guidance is provided for the management of these patients.