Crohn’s disease (CD for short) is still an incurable disease. Because of this, long-term maintenance therapy is needed to prevent relapses and reduce complications. The spectrum of disease in patients with CD is very broad, and the severity of the disease varies widely. For a few fortunate patients, surgical intervention may result in a long period of asymptomatic remission. However, for most patients, they will suffer from symptoms for years or even decades. Is there a point beyond which maintenance therapy is no longer relevant? Currently, there are only a few controlled clinical trial data on medical maintenance therapy beyond a few years. The main obstacle why this question has not been answered is that there are no accurate criteria for predicting the clinical course of CD for any individual patient. The main drugs used for CD treatment are: glucocorticoids, 5-aminosalicylic acid, and azathioprine/6-mercaptopurine (AZA/6-mp). First, hormonal therapy is ineffective in maintaining remission. Collaborative CD clinical trials in North America and Europe have clearly shown that hormones do not maintain disease remission. Although budesonide reduced the relapse rate at 3 and 6 months of treatment, the relapse rate at 12 months did not differ from the control group. A recent meta-analysis showed that glucocorticoids were completely ineffective in preventing relapses. Studies from Europe likewise showed no significant benefit of salazosulfapyridine on the duration of remission in CD, and Meta-analysis showed a small but statistically significant difference in CD remission induced by medical therapy with mesalazine. However, the NNT value was 16, so this statistical difference was clinically negligible. AZA/6-mp has relatively good evidence-based medical evidence to support long-term maintenance therapy. A careful, case-by-case analysis revealed that all studies showed a clear clinical benefit at 4-5 years of maintenance, with a progressive increase in relapse rate over time after discontinuation of treatment. the NNT for maintenance treatment with AZA was 7. The relapse rates at 1, 3, and 5 years after discontinuation of AZA treatment were 37%, 56%, and 65%, respectively. Remission can be regained after re-treatment. Despite the potential toxicity of long-term immunosuppression, the available evidence strongly suggests that the benefits of long-term maintenance therapy with immunosuppression far outweigh the harms, although AZA therapy appears to have no significant impact on long-term surgical intervention. CD is less like a disease and more like a group of diseases with similar symptoms in different genetic susceptibilities. Therefore, it is unlikely that any particular maintenance regimen will be effective in all or most patients. Patients with mild disease, with a low risk of serious complications and recurrent relapses, may benefit less from long-term maintenance therapy. Other patients with more severe disease, with stenosis or perforation complications, and with a higher risk of recurrent recurrence, rarely in remission, may benefit considerably from controlling their disease. Thus, the challenge is to identify those who are likely to have more severe disease and to treat them aggressively in the short and long term. Some current studies suggest that certain clinical characteristics of CD, such as age at diagnosis, interval since last relapse, smoking, and recent glucocorticoid application, may be predictive of disease relapse, but these speculations are not yet well established. It is hoped that the development of genotype-phenotype relationships will help provide a more accurate predictor of disease behavior and provide a more rational approach to how patients are selected for long-term maintenance therapy. So, just how long should maintenance therapy be for patients with CD? Currently, for patients with mild disease, experts recommend trying to stop treatment after a few years to see if maintenance therapy is really necessary for that patient. For patients in remission on immunosuppressants, maintenance therapy should be at least 4 years, and after 4 years of sustained remission, if the patient wishes to stop treatment, it is reasonable to try to discontinue therapy at this time if close follow-up is assured. However, immunosuppression should be reapplied as soon as symptoms recur. There is no unanimous opinion on the maintenance treatment regimen after surgery. Some experts recommend that colonoscopy should be repeated 6-12 months after surgery. Patients with endoscopic anastomotic recurrence are treated with immunosuppressive agents, while patients without endoscopic recurrence are closely followed. If remission is maintained for 4-5 years after surgery, discontinuation of therapy may be tried. Follow-up colonoscopy is performed on average once a year after discontinuation of treatment, and restart of treatment is recommended in case of significant endoscopic recurrence.