What is acceptable? Normally its polo shirts and khakis, but its getting colder out. Its an IT department, but business casual, and I hate wearing collared shirts and tucking them in. A sweater would be great, fixing both. I've been told that its ok to just wear a tshirt under a sweater, but it seems a lot of the older people do the whole collared dress shirt underneath thing. Actually looking around most wear long sleeved button down shirts. What is the protocol for sweaters?