The current trend for men’s fashion seems to be layers. Even during the summer in 70-80 degree weather. One needs to be aware of what materials will still breathe and now allow sweat spots or stains. For casual office that can easily transfer to happy hour or a night out Linen or tropical wool during the summer is the way to go. Layering can also go backwards (short sleeve over long sleeve) as long as you are conscious that you can’t take your jacket off.