Do you or don't you? For me, it depends if the dish needs to be reheated. I've reheated fish at work and it wasn't an issue but I only reheat fish like tilapia and cod that are fairly low on the fishy smell scale. I don't hesitate to eat a chilled tuna or salmon mayo based type salad or chilled fish over greens. No one ever complains and they often inquire as to what smells so good since the place is usually filled with the smells of takeout subway or burgers. What's your policy on bringing fish based lunches to work?