FSP has a new post up about crying students here.
I mentioned before that I am a bit of a crier. It's not that I'm emotionally unstable - I have a naturally sunny disposition and I tend to return to that state readily. But if I'm short on sleep and am feeling overwhelmed by a particular situation and I receive a blast of negative emotion from someone else, I will likely tear up. If I'm not able to take a quiet minute or two to pull myself together, then it becomes a horrible feedback cycle and I turn in to a sobbing, snotty mess and will take quite a bit longer to pull myself together.
I have never cried in a professor's office. I wasn't inclined to solve problems in professor's offices as an undergrad, and by the time I was a grad student, I had enough experiences with the possibility of screwing up very expensive projects and/or getting someone seriously hurt that I didn't worry inordinately about grad school stuff.
But I do have painful experience (unfortunately, significantly more experience than when I wrote that post 4 years ago) with crying in the field in front of other people, especially as the person in charge of something big that has all gone to shit. Not in the middle of the crisis - then I'm too busy managing it. But afterward, when the recriminations start...
So how to deal with someone who is crying in the field?
1. Offer something resembling tissues (grubby paper towels, most likely)
2. Ask if they need a minute.
3. Give them a minute.
For criers like me, tears are a similar response to yelling or throwing things. Hovering anxiously, attempting hugs (if I'm crying at work, my personal space has just doubled. No hugs!), and generally making a big deal of everything is counterproductive. Usually the best thing is to let the venting happen and then get back to work.