RebiSmart™ is a device with an electronic injection log to monitoring adherence to therapy. Therefore RebiSmart is a tool for administering Rebif in multi-dose cartridges that may improve patient satisfaction and adherence to therapy. The objectives of this study are to evaluate adherence, effectiveness and convenience of treatment in subjects with relapsing multiple sclerosis (RMS) using RebiSmart to self-inject Rebif in a multi-dose cartridge.