Early, close monitoring and treatment can slow or prevent disease progression in patients with inflammatory bowel disease (IBD) who are at high risk of developing complications. Therefore, it is important to identify high-risk factors for complications at the initial diagnosis or during the course of the disease. The IBD Ahead initiative conducted a detailed literature review to analyze predictors of long-term prognosis in patients with IBD and drafted an expert consensus opinion. The consensus opinion was revised at an international congress by IBD experts from 32 countries and finally finalized at an international meeting in November 2014. RESULTS: For patients with Crohn’s disease: young age of onset, extensive lesions, deep ulcers, ileal/ileocolonic involvement, perianal and/or severe rectal lesions, and penetrating/stenotic lesions should be considered as high risk factors for complications. In patients with ulcerative colitis: young age of onset, extensive colitis, frequent episodes requiring hormonal or hospital treatment, etc. increase the risk of colectomy or re-hospitalization. Smoking, co-morbid primary sclerosing cholangitis, and co-infections may influence the disease process. Available genetic and serological markers are not accurate and have no clinical predictive value. Simple general and clinical characteristics can assist clinicians in screening patients at high risk for complications during diagnosis and treatment. However, many risk factors originate from retrospective studies and are unvalidated, and appropriate prospective studies are needed to provide evidence for clinical decision making and to truly predict disease progression in each patient.