Hi,
I have been working as a web designer for the past one year. (designing alone not dev.). I want to do some certifications(international standard) in the same to add my value.

can anybody suggest me, which certification is the best one now a days, related to web design? If i get the self study kit (like book or video tutorials), still that will be better.

(FYI: software knowledge-Photoshop, Dreamweaver,flash)

Thanks.

IMO, certifications are mostly worthless. If you don't have plenty of good, real-world, hands-on EXPERIENCE, a certification is just a piece of paper and won't help you. Most hiring managers (at least around here) have no clue what 'web design' really means anyway, a certification tacked on would be equally meaningless.