I work in an office where the dress code is business/casual. I usually wear a button up shirt or sometimes a polo. Here lately I have been carrying 1 folder and 1 fixed blade at all times.
The folder is always either a spyderco wegner, a rekat pioneer, or a rekat sifu. The fixed blade is either a tops street scalpel, a greco companion, or a trace rinaldi sharktooth.
The shirt tail is always un-tucked, and always covers up both blades with no problems. I doubt anyone even knows I carry a knife up there. If I need to use a knife at work, I always use the folder. If some drug fueled psychopath attacked me though, it would be the fixed blade that did the dirty work.
So, in other words - try to go *concealed*. What they don't know won't hurt 'em. It also depends on how much risk you're willing to take though. If you think you would get fired if someone spotted your blade, don't risk it unless you're willing to look for another job.
If you have to be a "suit and tie guy" every day, consider a folder that will fit all the way in your pocket. A clip sticking out is sure to draw comments... If you plan on USING the knife openly, I'd definitely go with something "non tactical".
whatever you decide - good luck!