My previous job was not in the private sector, so, here we go:
The pressure is different. At my previous job, I put pressure on myself to succeed, here, I don't have to do that...
The only topics of discussion in the new office at structural engineering and money. And not always in that order. And it's usually the boss who initiates all discussion. The rest of the place is too busy working on structural engineering to talk or think about anything else.
No one plays music at their desk.
No one make jokes, unless it's an anecdote about structural engineering.
No one surfs the web unless it's 100% related to structural engineering AND money. Meaning, no surfing Eng-Tips unless it's from home.
E-mail traffic doesn't seem to include ANY work-spam (chain letters) or other junk.
People come to work if they're sick. I have seen three people who appeared to have been well on their way through the flu to pneumonia.
People do seem to take vacations, though they make very sure that someone will pick up their work when they're gone - so does the boss and he's deadly serious about it.
Coffee is free 24/7 - and you better be ready to work 24/7 if necessary.
At least once a week there is a seminar given either by some vendor or similar. Food is often included.
I have the idea that everyone is paid very well - with excellence expected in return. No one talks about pay, pay "grades" or other seniority. There are a lot of offices with doors, though, clearly indicative of being at a higher level in pay/responsibility.
The challenges for me are a) I have to be faster, b) don't ever get angry at anyone - only the boss is allowed to do that, c) always ask for a deadline, but never expect to be given one ("whenever you're done" translates into "stop wasting time and money asking me for a deadline, you could've spend those two seconds working on the problem"), d) don't ever get sick, and e) document my work on my own time; the boss doesn't need a memo detailing what I've done, how I've done it or anything else.
I am not in a celebratory mood, I am terrified that I'm going to get fired. I'm a good swimmer, but it's going to take getting used to the boss' foot on my head while I'm trying to stay afloat, if you know what I mean. I worked in private a long time ago, but I was mostly in the field and had a lot of "free time" - like driving to and from jobsites and such - this is a whole new ball game for me.
