Microsoft Certifications are available for most Microsoft technologies and skill levels from students to business workers to IT professionals, developers, technology trainers, and system architects.
"MOS (Microsoft Office Specialist) certification features Web-based pretests, program-specific certification exams, and a series of Microsoft Press step-by-step books that help you demonstrate expertise in accomplishing essential job tasks across multiple programs. After earning an MOS certification, you receive access to a member Web site where you can print transcripts to demonstrate proof of certification and receive a certificate that verifies your successful completion of the exam. Additionally, professionals who earn this certification gain access to a certification logo that they can display on their resumes and other business materials."
More Info: MOS