The answer to this question strongly depends on the specific industry for which you are applying. Your attire should give the overall impression that you are neat, professional, and polished. You are aiming for an outfit that is one step above what you might wear to the job every day. Be sure personal hygiene details like a fresh haircut, manicure and a clean shave are covered. If you are not sure between two outfits, go with the more formal choice. Too dressed up is less of a risk than under dressing for the big day.