Pic Pick: Straight to the Point in Vienna
The Viennese don't mess around. It must be a Germanic thing. You know, efficiency and organization.
As a result, the U-Bahn in Vienna runs pretty much like clockwork. Similarly, the signage on the trains doesn't miss a beat or leave any room for misunderstanding. Seen above (and snapped by us), the pictures indicate that you should give up the specified seats to the pregnant, those with small children, the disabled, and the elderly.
And just in case you have any question about what constitutes disability, they've come up with a handy universal symbol for it. Not only is the gentleman in blue blind, but he's got one bad hip and an armband that seems to indicate he's radioactive, too.