This study determined the diagnostic utility and hospital resource impact of plain abdominal radiography in emergency department patients with suspected appendicitis. The authors reviewed medical records of 821 consecutive patients hospitalized for suspected appendicitis; 78% had plain abdominal radiography. Sixty-four percent had appendicitis. Radiographic findings were noted in 51% of patients with, and 47% of patients without appendicitis; no individual radiographic finding was sensitive or specific. Specific conditions were suggested in 10% of impressions; these failed to correlate with final clinical diagnoses 57% of the time. Hospital cost per abdominal radiograph was $67; cost per specific, correct radiographic diagnosis was $1,593. This is compared with $270 per appendiceal computed tomography scan (based on recent literature data). The authors conclude that plain abdominal radiographs in patients with suspected appendicitis are neither sensitive nor specific, are frequently misleading, are costly per specific and correct diagnosis, and should not be routinely obtained on patients with suspected appendicitis.