If you're translating English business cards into Korean, work with a professional who understands the intricacies of the task and asks enough questions to be able to translate job titles correctly.
For example, here are many (but not all) of the possibilities for translating "director" and its variants:
Some of these correspond with other possible English job titles, too. For the full run-down, check out "How Do You Write 'Director' in Korean?
"Director" is not the only confusing job title (admittedly, it is one of the harder ones though). This is not just because Korean organizations are structured differently than Western ones; you'll also find that even the same jobs at the same level in the organization can sometimes imply different responsibilities.
I'd like to point out too that Koreans aren't always helpful here since they tend to inflate their English job titles. I was at a (very well-known!) company recently where, of the ten business cards I was given by my Korean counterparts, every one but the president's card listed him or her one rank higher in English than his/her card in Korean! It takes an honest broker to work through all this sometimes.
Korean Translation Tip - Don't consider a business card translation a throw-away job just because the job title is only one word. Get professional help (such as from someone with a masters degree from a Korean university in management strategy).
BTW, I've even written a guidebook for this, which can be downloaded free: The Definitive Guide to Business Cards in Korea.