Sherry T who has been "given a talking to" suggests:

Always wear a burgundy, green, brown, etc. color with black.

Axis who's fortunate to work in a "business casual" environment yet also had "the attire chat", suggests:

Men: If you pull your hair back (mine is 14", one length) into a ponytail, then remove your excess earings because they will be in full freaking view of everyone. I keep two on the left side, removing all others.

Perry Ellis Executive shirts have decently long collars and drape. Great purple, blue, crimson and black colors with excellent hues. Dark dress shirts are acceptable in my office.