A Non-Interventional Clinical Study to Evaluate Long-Term Safety and Effectiveness of HUMIRA (Adalimumab) in Pediatric Patients With Moderately to Severely Active Crohn's Disease (CD)

* For a patient enrolling into the HUMIRA treatment group; A pediatric patient between the ages of 6 and 17 years inclusive at the time of enrollment, diagnosed with moderately to severely active CD who has been prescribed Humira therapy according to the routine clinical practice. * For a patient enrolling into the immunosuppressant therapy treatment group; A pediatric patient between the ages of 6 and 17 years inclusive at the time of enrollment, diagnosed with moderately to severely active CD who has been prescribed azathioprine, 6-mercaptopurine or methotrexate. * Parent or guardian; or patient (if 18 years of age or older at enrollment and rolling over from an AbbVie-sponsored investigational Pediatric CD investigation trial) has voluntarily signed and dated an Authorization for Use/Disclosure of Data (AUDD)/informed consent form (ICF) after the nature of the registry has been explained and the patient, patient's parent or legal guardian has had the opportunity to ask questions.

* Patients should not be enrolled into the registry if they are currently being treated with any investigational agents or are receiving any investigational procedures. * Patients should not be enrolled into the immunosuppressant therapy treatment group if they require ongoing treatment with approved biologic agents including HUMIRA.