Little attention has been paid to developing prediction rules that could assist in deciding which patients with community-acquired pneumonia (CAP) need intensive care. Four existing prediction rules were examined to determine if any could predict the need for intensive care in these patients. The prediction rules studied were British Thoracic Society (BTS), Conte et al, Leroy et al, and Fine et al. Thirty-two patients admitted to the medical or coronary intensive care unit (ICU) during 1 year with pneumonia Diagnosis Related Group 079 or 089 were evaluated. The sensitivity of each rule for identifying a need for ICU admission in our group was BTS .72 using both rules together, Conte et al .47, Leroy et al .56, and Fine et al .84. It was concluded that these rules poorly identify the need for ICU admission for patients with severe CAP. Of the 4 rules tested, the BTS rule was the simplest, and the Fine et al rule was the most sensitive. None of them performed well enough to be used for decision making in individual patients.