I once interviewed for a job, turned down the offer. A year later, got in touch, and they were eager to bring me on board. Worked there for two years and there were absolutely no hard feelings. Many managers are not petty and are just interested in hiring talented people.

I've not quite had this experience, but similar, and agree - if you've got what they want, then they'll be happy to receive your call. (As long as you're polite about it!)

Don't listen to your friends blindly on this. It depends. If you accepted it, signed the paperwork and then 1 day before, you decided not to join, it could burn bridges with that particular group/manager. But turning down employment is totally acceptable in cases where you have multiple options and you decide what is best for you. It is totally ok to go for an interview and then decide if you want to join or not (if they do give you an offer).

Yes. And don't date someone unless you know you are going to marry them. ;-)

Job interviews are "dates" - you are checking each other out. If your date goes poorly, yes you probably won't get another date with that person - but you might with her sister.

In other words, the same manager probably won't hire you but it shouldn't keep you from being hired by another group in the same company. If you turn down a QA job you won't be blacklisted (that I'm aware of).

There's an easier way to make both sides happy. Instead of "interviewing," suggest that you come and check the place out, talk to employees, and just get a feel for the company.

If you like it, follow up with an interview. If not, no expectations are broken, and no one gets hurt.

Ah, I wish this were so easy! Perhaps it's a certain lack of kahunas, but I never felt like it would be appropriate to ask the recruitment agent if I can swing by... plus, now in my consulting gig (sub-contractor) I get a call, hop on a plane, and go work someplace. (That said, no interview...)

In the Netherlands it is pretty common to do multiple interviews and only agree to taking a job after hearing back from all the companies. This way you may have to turn down multiple offers. I don't know if this is normal in the US.

Thanks for the info guys, appreciate it!

It could be considered burning a bridge on the way you handle the situation. I would turn down the job, but do it in a way where I make myself look good doing it. I interview for the job, then let them know that you are very interested in the job, but due to prior work commitments you have to decline at the moment. You can tell them that you are in a serious project and that you are a crucial part of it. The project would be undermined if you abruptly leave. You can explain that you wouldn't want to leave in that type of situation and could explain there is currently not a set deadline. There would be other ways to handle it as well, and always keep in contact even if it's infrequent. You never know what circumstances may arise where you will need to find work right away.