• Improvement/resolution of signs and symptoms of the acute Crohn's disease (CDAI -100), [ Time Frame: Months 0, 3, 6, 9, 12, 18, 24 ] [ Designated as safety issue: Yes ]
• Compliance with the self-injection via the HUMIRA-PEN, [ Time Frame: Months 0, 3, 6, 9, 12, 18, 24 ] [ Designated as safety issue: No ]
• Rate of adverse events [ Time Frame: Months 0, 3, 6, 9, 12, 18, 24 ] [ Designated as safety issue: Yes ]
• Long-term improvement of patients Quality of Life [ Time Frame: Months 0, 3, 6, 12, 24 ] [ Designated as safety issue: No ]

This study is intended to evaluate the long-term safety and effectiveness of adalimumab in Crohn's Disease patients who are treated as recommended in the product label.

Subjects are to be treated in accordance with the most current local product label. Patients will be seen at the site at study enrollment and then at routine office visits through completion of the study (up to 5 years). Subjects will be followed according to normal clinical practice. Adverse events of interest (including reports of opportunistic infections, such as tuberculosis [TB], other serious infections, occurrence of intestinal stricture, new malignancies, lupus/lupus-like illness, demyelinating disorders, congestive heart failure), and serious adverse events (SAE) will be recorded throughout the study. In addition, adverse events of interest will be reported at any time after the last dose if the Investigator believes the event to be related to adalimumab treatment.

Information to evaluate the effectiveness of adalimumab therapy will be collected through administration of patient-reported outcome measurements (PROs) and Physician assessments of disease activity if assessed as part of clinical practice at the study enrollment visit and at subsequent routine visits. The following PROs will be used: Short Inflammatory Bowel Disease Questionnaire (SIBDQ), Health Care Resource Utilization and Work Productivity and Activity Impairment. The Physician's assessment of disease activity will be collected using the Physician's Global Assessments Form. Information about medications taken for CD will be collected.

Community sample: patients with Crohn's Disease

Inclusion Criteria:

• Severe, active Crohn's Disease in patients with insufficient response to a complete and adequate therapy of glucocorticoid and/or immunosuppressive drug and/or hypersensitivity against such a therapy or in patients where such a therapy is contraindicated.

Exclusion Criteria:

• Hypersensitivity against the drug or one of the other ingredients
• active tuberculosis or other severe infections (e.g. sepsis and opportunistic infections)
• Moderate to severe cardiac insufficiency.