Is the office in which you work ok with CCW or firearms in general? If they are not then the bathroom trick might work. If they are ok on either front then just do as mentioned and leave it in your drawer/book thing. Can't imagine a lawyer that is not ok with CCW.
I am a lawyer and I office downtown. (Midtown really, 13th and Shartel) Everyone in my office knows I carry and knows where to find a firearm if they need one. I come in with new toys every so often.
We own the building though. Might be a bit different.
Gosh, that would be great, but no the office doesn't know....