Background/Aims: The purpose of this study is to determine the effectiveness of extensive nonsurgical management of patients with clinically active Crohn’s disease of the terminal ileum and to identify parameters that could predict failure of this nonsurgical approach. Methods: All consecutive patients hospitalized for the first time because of active Crohn’s disease of the terminal ileum between 1985 and 1994 were included. Two groups of patients were defined. Patients who responded favorably to the extensive treatment protocol (group I), and patients in whom an ileocolic resection had been performed (group II). Treatment and patient characteristics were related to outcome. Results: Twenty-nine (38%) of the 76 patients were treated successfully by nonsurgical management (group I) and did not have surgery until the end of follow-up (mean 8.0 years, range 3–12 years). In total, 47 patients (62%) had ileocolic resection (group II). Logistic regression analysis revealed that a longer time between onset and exacerbation of this disease, the presence of stenosis and extraintestinal manifestations were independent predictors of failure of nonsurgical treatment. Conclusion: Prolonged medical treatment is effective in only one third of the clinically admitted patients. It should be applied with caution particularly in patients exhibiting stenosis, extraintestinal manifestations or a known history of Crohn’s disease of more than 5 years.