An Observational Study for the Assessment of Adherence, Effectiveness and Convenience of Rebif® Treatment in Relapsing Multiple Sclerosis Patients Using RebiSmart™.

Inclusion Criteria: * Males and female subjects between 18-65 years of age (only in Germany: Males and females between 12 - 65 years of age in order to follow national medical society guidelines) * Female subjects must be neither pregnant nor breast-feeding and must lack child-bearing potential as defined by either: a) Post-menopausal or surgically sterile, or b) Using a highly effective method of contraception for the duration of the study. This is defined as a method that results in a low failure rate (i.e., less than 1% per year) when used consistently and correctly, and includes for instance implants, injectables, combined oral contraceptives, intra-uterine device (IUD), sexual abstinence or vasectomised partner * Subjects diagnosed with Relapsing MS according to the revised McDonald Criteria (2005) * MS-treatment naïve subjects or subjects treated with Rebif multi-dose injected by RebiSmart for no longer than 6 weeks prior to Baseline visit * Subjects that are able to self-inject with RebiSmart (in the opinion of the physician) * Subjects with Expanded Disability Status Scale (EDSS) score \< 6 (inclusive) at Baseline * Signed informed consent (in countries where subject signature is not mandatory: subject must be given the patient information) Exclusion Criteria: * Subjects experiencing a relapse within 30 days before Baseline * Subjects who have participated in other studies within 30 days before Baseline * Subjects who received any MS therapy within 6 months prior to study enrolment (e.g., other disease modifying drugs: immunomodulatory, immunosuppressive agents or combination therapy) with the exception of Rebif multi-dose injected by RebiSmart * Any visual or physical impairment that precludes the subject from self-injecting the treatment using the RebiSmart * Pregnancy and breast-feeding * Serious or acute heart disease such as uncontrolled cardiac dysrhythmias, uncontrolled angina pectoris, cardiomyopathy, or uncontrolled congestive heart failure * Current or past (within the last 2 years) history of alcohol or drug abuse * Have any contra-indications to treatment with interferon beta-1a according to Summary of Product Characteristics