Repair of complex incisional hernias characterized by large and/or multiple defects, multiple recurrences, obesity, and extensive intra-abdominal adhesions pose major challenges. AIMS: To review outcomes of the modified Rives-Stoppa repair of complex incisional hernias. METHODS: We maintained an IRB-approved, prospective database of patients undergoing modified Rives-Stoppa, mesh-based repair of complex incisional hernias from 1990-2003. Prostheses were placed, whenever possible, intramurally, i.e. posterior to rectus muscle but anterior to posterior rectus fascia; some were fully intraperitoneal. Patients were followed prospectively through clinic visits and mailed questionnaires. Follow-up data obtained via chart review was complete in all patients, and 87% of patients completed and returned the questionnaire. Mean follow-up was 70 months (range 24-177 months). Primary outcome measures were 30-day perioperative mortality, morbidity, and hernia recurrence. Secondary outcome measures were duration of stay, peri-incisional pain at follow-up, and patient self-reported satisfaction. RESULTS: 254 patients underwent Rives-Stoppa mesh repair. The most frequent comorbidities were morbid obesity (33%), diabetes (16%), and chronic obstructive pulmonary diseases (8%). 30% of the patients had one or more prior failed hernia repairs. Prostheses included polypropylene (75%), polypropylene/ePTFE (14%), and ePTFE (9%) depending on presence/absence of intraperitoneal exposure. Mean mesh area was 744±26 cm2. Mean hospital stay was 6 days. Mortality was zero and overall morbidity was 13% (wound infection-4%, acute mesh infection-3%, and seroma-hematoma-4%). Overall hernia recurrence rate was 5% (includes mesh infections requiring mesh explanation). Risk factors for hernia recurrence were postoperative wound/mesh infection (31% vs 4%, p=0.003) and respiratory comorbidities (25% vs 4%, p=0.007). Risk factors for mesh infection included bowel resective procedures or enterotomies at time of mesh implantation and history of prior mesh infection. 27% of respondents reported intermittent pain (average worse-episode score of 4.7 on standard 0-10 pain scale), yet 89% reported overall satisfaction with their repair. CONCLUSIONS: The modified Rives-Stoppa repair of complex incisional hernia is safe with low recurrence rate (5%) and high patient satisfaction. Risk factors for hernia recurrence were postoperative infection and respiratory comorbidities. Permanent mesh should not be used in patients at high-risk for infection or even in a clean-contaminated field.