This particular situation was difficult for me, because I did not arrive on time for the party. By the time I showed up everyone was already eating and drinking and all of the food and drinks were on the same bill.

I agree though that it's best to be as proactive as possible. Asking upfront for separate checks let's everyone know that they are responsible for their own tabs.

Funny enough, the coworker I mentioned earlier started ordering much less expensive meals once we started splitting up the check.

I guess the key is to speak up as soon as possible in a get together like this one. If you wait too long you might end up paying more than your fair share.

In this vein, I have a sister-in-law who is habitually late for family get togethers. I think that she feels more important if she makes other people wait for her. We used to let it ruin our get togethers. There is nothing like cooking a huge meal and watching it get cold and hearing people complain about being hungry while waiting AGAIN. NOW, we know to give her a time an hour before the time we give everyone else.

You really can't change other people in life. What you must strive to do is change your own actions.

I wanted to add, that your server will most likely love it if you ask for a seperate tab. As a waitress for years in college, i definately noticed I got more tips when everyone was paying their own bill.