This randomized placebo-controlled double-blind, multi-centre trial will determine the efficacy of the probiotic VSL#3 in the prevention of Crohn's disease development following surgical resection and re-anastomosis. A total of 120 patients will be randomly assigned in a 1:1 ratio to receive VSL#3 or placebo for 90 days. Patients who respond to study treatment, as defined by the absence of a severe endoscopic recurrence at day 90, will be offered open-label VSL#3 for an additional 9 months.

Inclusion Criteria:

1. Subjects 16 years of age or older
2. Diagnosis of Crohn's disease
3. Resection of ileocolonic Crohn's disease and small bowel to colonic anastomosis within 30 days of randomization
4. Able to provide informed written consent
5. Women of child-bearing potential with a negative serum pregnancy test, and/or use of effective contraception

Exclusion Criteria:

1. Use of perioperative steroids in tapering doses and anti-diarrheal agents
2. Treatment with a TNF-antagonist in the 8 weeks prior to resection
3. Clinically significant Crohn's disease elsewhere in the GI tract
4. Clinically documented short bowel syndrome
5. Serious disease other than Crohn's disease
6. Impaired liver or renal function
7. History of cancer with less than 2 years disease-free state
8. Abnormal Laboratory values
9. Alcohol or drug abuse
10. Some psychiatric conditions
11. Patients using other study medications
12. Patients who are unable to attend study visits or comply with study procedures
13. Positive pregnancy test