PURPOSE: A survey was conducted to document current medical treatment of patients with uncomplicated acute diverticulitis. METHODS: A survey was mailed to 667 fellows of The American Society of Colon and Rectal Surgeons certified by the American Board of Colon and Rectal Surgery. Queries were based on a clinical scenario of a patient with uncomplicated diverticulitis. RESULTS: Three hundred seventy-three surveys (56 percent) were returned completed. The majority (66 percent) chose an abdominal computed tomographic scan as the initial diagnostic test. One-half used a single intravenous antibiotic with second-generation cephalosporins (27 percent) and ampicillin/sulbactam (16 percent) being the most common. Oral antibiotics given at discharge were ciprofloxacin (18 percent), amoxicillin/clavulanate (14 percent), metronidazole (7 percent), and doxycycline (6 percent). Combinations chosen were ciprofloxacin/metronidazole (28 percent) and metronidazole/trimethoprim sulfamethoxazole (6 percent), whereas 21 percent chose a variety of other antibiotics. The majority (74 percent) prescribed oral antibiotics for 7 to 10 days. Dietary recommendations at discharge were low residue (68 percent), regular (21 percent), and high residue (10 percent). Half of those surveyed believed avoidance of seeds and nuts were of no value. Follow-up examinations chosen included sigmoidoscopy and barium enema (29 percent), colonoscopy (25 percent), sigmoidoscopy (17 percent), barium enema (13 percent), and other (16 percent). Sixty-five percent of colon and rectal surgeons claim to handle more than half of their patients with uncomplicated diverticulitis on an outpatient basis. CONCLUSION: Variations in the management of uncomplicated sigmoid diverticulitis are noted among colon and rectal surgeons, especially in terms of antibiotic choice, discharge instructions, and follow-up outpatient studies. The survey results are compared with the conclusions reached in The American Society of Colon and Rectal Surgeons practice parameters. Documentation of practice pattern variation may serve as an educational tool for physicians to improve their quality and cost of medical care. Consideration should be given to better publicize already existing American Society of Colon and Rectal Surgeons practice parameters for this common entity.