Over the last few years, much light has been shed on the pathogenesis of Crohn´s disease. Further knowledge in this field has provided a firm basis not only for understanding of current treatment but also for development of new therapeutic strategies. The aim of these new agents is primary selective interaction with key processes of intestinal inflammation. At present, only anti-tumor necrosis factor-alfa antibodies namely infliximab, is licensed for clinical practice. The attention is focused on the early (top-down) or late (step-up) use of biological agents. As yet, early use of biological agents remains to be supported by convincing evidence, nevertheless it may be advocated as first-line therapy for newly diagnosed severe Crohn´s disease patients, both adults and children.