"Talk
To Each Other, not About Each Other" when you have an issue with a co-worker.
Went over JUST GREAT with two of the three gossip queens where I work! I brought it up during one of our monthly staff meetings last year. Now they won't even look at or talk to me unless it's specifically work related, like "This rack of mdse is ready for the sales floor". Yet they are bubbly and friendly toward everyone else in the back room.
I have worked at my present employer for over 3 years, and have seen 90% employee turnover since starting there - most of it right after completing my first year. Among the only people still there when I started are these two drama queens in the back room. They do good work at what they do every day, it's just too bad their mouths run as fast as their hands!
I've seen some really great part/full-timers come and go within weeks in this place, even an assistant manager. I got along with most of them quite well, had some fun out in the sales area where I work, but mediocrity seems to outlast them all.