IT professionals and developers worldwide become Microsoft Certified Professionals (MCP's) because they know that employers, clients and the IT industry acknowledge their expertise in working with Microsoft products and technologies.

Click on the following links to see why MCP's are nowadays so popular in the IT market: 

Microsoft Chief Operating Officer Kevin Turner talks about the importance of certification

What Microsoft customers say about the value of Microsoft technical certifications.

The many benefits of Microsoft Certification, as articulated by real Microsoft Certified Professionals (MCPs)