Although uncommon, diffuse jejunoilietis is one of the most difficult areas in Crohn's disease (CD) to treat. Although the exact frequency is unknown, most gastroenterologists believe that its prevalence has been underestimated and that it may have an increased incidence among children and young adolescents. The clinical importance of this clinical disease phenotype is the impact diffuse small bowel disease is expected to have on a child's growth and development. Moreover, patients with jejunoileitis are more likely to experience complications, including fistulization, and most commonly, intestinal obstruction. The associated morbidity and frequent need for surgical intervention renders these patients at risk for intestinal insufficiency. Although stricturoplasty has reduced the incidence of short bowel syndrome, most patients with proximal small bowel CD still require repeated surgical intervention. Jejunoileitis represents a distinct clinical phenotype within the heterogenous family of disease phenotypes considered as CD. Whether a specific genotype will be found to associate with jejunoileitis remains to be determined. Through the development of novel diagnostic techniques, including gadolinium enhanced magnetic resonance imaging (GMRI), enteroscopy, and capsule endoscopy, the mean age at diagnosis is expected to decrease. Coupled with an increase in clinical suspicion, early diagnosis may allow physicians to consider implementing aggressive immunomodulatory therapy. Future studies are needed to determine if the early detection and use of immune modulators in patients with proximal small bowel disease will improve overall quality of life and decrease the risk of nutritional and surgical comorbidity.